Draft California 2026 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 7 - Colorado River Basin Region

Water Body Name:	Havasu, Lake
Water Body ID:	CAL7140000020040823161128
Water Body Type:	Lake & Reservoir


DECISION ID	158732	Region 7
Havasu, Lake

Pollutant:	Oxygen, Dissolved
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Eleven of the 48 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Eleven of the 48 samples exceed the threshold.and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

334090

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Colorado River Basin, WARM Water Habitat Objective, Chapter III, states the following: The dissolved oxygen concentration for warm water habitats shall not be reduced below 5.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

335711

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Colorado River Basin, Cold Water Habitat Objective, Chapter III, states the following: The dissolved oxygen concentration for cold water habitats shall not be reduced below 8.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

334083

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 8 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

126735

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Oxygen, Dissolved.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Colorado River Basin, WARM Water Habitat Objective, Chapter III, states the following: The dissolved oxygen concentration for cold water habitats shall not be reduced below 5.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

126734

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 4 of 5 samples exceeded the water quality standard for Oxygen, Dissolved.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

5137

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Forty-nine measurements were taken at 3 locations on the lake, generally collected from 8/20/1992 through 3/14/2006. Thirty-one measurements could not be used in the assessment because insufficient spatial information was collected and it could not be determined if the sampling locations were within the state boundaries. The 18 acceptable measurements were collected from 5/1995 through 3/2006. Of these acceptable measurements, 2 exceeded the Basin Plan Objective. The exceedances were found in measurements collected on 7/06/2000, and 1/28/2004, from one location (USEPA, 2007).

Data Reference:

Data for organic and inorganic chemicals in water samples collected from waterbodies located in the Colorado River Basin-Region 7, collected and reported by the Arizona Department of Environmental Quality and reported on the USEPA Storet system. 1995-2004.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: The dissolved oxygen concentration shall not be reduced below the following minimum levels at any time: For water designated for both WARM and COLD Beneficial Uses... 8.0 mg/l (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Measurements were collected from the following Lake Havasu locations: near the north end (100100, 100101),and midlake (100099). Insufficient spatial information was collected for sampling locations 100100, and 100099 to determine if the sampling locations were within the state boundaries.

Temporal Representation:

Fortynine discrete measurements were collected. Measurements were generally collected from 8/20/1992 through 3/14/2006. Measurements were collected on 2 discrete dates in 1992, 1 date in 1993, 2 dates in 1994, 17 dates in 1995, 9 dates in 1996, 3 dates in 1997, 3 dates in 1998 , 2 dates in 2000, 4 dates in 2001, 2 dates in 2002, 3 dates in 2003, 1 date in 2004, and 1 date in 2006. The exceedances were found in measurements collected from 7/06/2000 and 1/28/2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

334089

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

335700

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158732, Oxygen, Dissolved	Region 7
Havasu, Lake

LOE ID:

334085

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 4 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155140	Region 7
Havasu, Lake

Pollutant:	1, 1-dichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155140, 1, 1-dichloroethane	Region 7
Havasu, Lake

LOE ID:

321248

Pollutant:

1, 1-dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

Surface Water Ambient Monitoring Program (SWAMP) Data for organic and inorganic constituents in water and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. May 2002-May 2005.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 1 mg/l Aluminum, 0.05 mg/l Arsenic, 0.0002 mg/l Benzo[a]Pyrene, 0.005 mg/l Cadmium, 0.0001 mg/l Chlordane, 0.05 mg/l Chromium, 0.6 mg/l o-Dichlorobenzene, 0.5 mg/l p-Dichlorobenzene, 0.005 mg/l 1,1-Dichloroethane, 0.006 mg/l 1,1-Dichloroethylene, 0.006 mg/l cis-1,2-Dichloroethylene, 0.01 mg/l 1,2-Dichloroethylene,-trans, 0.005 mg/l 1,2-Dichloropropane, 0.002 mg/l Endrin, 0.3 mg/l Ethylbenzene, 0.00001mg/l Heptachlor, 0.00001 mg/l Heptachlor Epoxide, 0.001 mg/l Hexachlorobenzene, 0.0002 mg/l Lindane/Hexachlorocyclohexane (HCH), 0.030 mg/l Methoxychlor, 0.013 mg/l Methly-Tertiary-Butyl Ether (MTBE), 0.02 mg/l Molinate, 0.070 mg/l Chlorobenzene (mono), 0.1 mg/l Nickel, 0.045 mg/l Nitrate, 0.001 mg/l Nitrite as N, 0.0005 mg/l PCBs (total), 0.05 mg/l Selenium, 0.005 mg/l Tetrachloroethylene, 0.07 mg/l Thiobencarb, 0.15 mg/l Toluene, 0.005 mg/l 1,2,4-Trichlorobenzene, 0.2 mg/l 1,1,1-Trichloroethane, 0.005 mg/l 1,1,2-Trichloroethane, 0.005 mg/l Trichloroethylene, and 1.75 mg/l Xylene (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155135	Region 7
Havasu, Lake

Pollutant:	1,1,1,2-Tetrachloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155135, 1,1,1,2-Tetrachloroethane	Region 7
Havasu, Lake

LOE ID:

320374

Pollutant:

1,1,1,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chloroform, Methylene Bromide, Bromochloromethane, Ethylene Dibromide, 1,1,1,2-Tetrachloroethane, 1,2,3,-Trichloropropane, 1,2-Dibromo 3-Chloropropane, 1,3-Dichloropropane, 2,2-Dichloropropane, or 1,1-Dichloropropene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155137	Region 7
Havasu, Lake

Pollutant:	1,1,1-Trichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155137, 1,1,1-Trichloroethane	Region 7
Havasu, Lake

LOE ID:

321256

Pollutant:

1,1,1-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155144	Region 7
Havasu, Lake

Pollutant:	1,1,2,2-Tetrachloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155144, 1,1,2,2-Tetrachloroethane	Region 7
Havasu, Lake

LOE ID:

319582

Pollutant:

1,1,2,2-Tetrachloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two samples were taken at 1 location in the interior of the lake. One water sample results could not be used in this assessment because the sample results were non-detect and the detection limit was above the criteria concentration. The one acceptable water quality sample was collected in 10/2002 at 1 location. This sample did not exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.001 mg/l Benzene, 0.0005 mg/l Carbon Tetrachloride, 0.0005 mg/l 1,2-Dichloroethane, and 0.001 mg/l 1,1,2,2-Tetrachloroethane (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155212	Region 7
Havasu, Lake

Pollutant:	1,1,2-Trichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155212, 1,1,2-Trichloroethane	Region 7
Havasu, Lake

LOE ID:

321257

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155212, 1,1,2-Trichloroethane	Region 7
Havasu, Lake

LOE ID:

320079

Pollutant:

1,1,2-Trichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two samples were taken at 1 location in the interior of the lake. One water sample result could not be used in this assessment because the sample results were non-detect and the detection limit was above the criteria concentration. The one acceptable water quality sample was collected in 10/2002 at 1 location. This sample did not exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 1.2 ug/l Benzene, 4.3 ug/l Bromoform, 0.25 ug/l Carbon Tetrachloride, 0.56 ug/l Dichlorobromomethane, 0.38 ug/l 1,2-Dichloroethane, 0.52 ug/l 1,2-Dichloropropane, 0.44 ug/l Hexachlorobutadiene, 0.80 ug/l Tetrachloroehtylene, 0.6 ug/l 1,1,2-Trichloroethane, and 2.7 ug/l Trichloroethylene (USEPA, 2000).

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155031	Region 7
Havasu, Lake

Pollutant:	1,1-Dichloroethylene (DCE)/ Vinylidene Chloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155031, 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride	Region 7
Havasu, Lake

LOE ID:

321258

Pollutant:

1,1-Dichloroethylene (DCE)/ Vinylidene Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155158	Region 7
Havasu, Lake

Pollutant:	1,1-Dichloropropene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155158, 1,1-Dichloropropene	Region 7
Havasu, Lake

LOE ID:

320386

Pollutant:

1,1-Dichloropropene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155204	Region 7
Havasu, Lake

Pollutant:	1,2,3-Trichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155204, 1,2,3-Trichlorobenzene	Region 7
Havasu, Lake

LOE ID:

319864

Pollutant:

1,2,3-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155155	Region 7
Havasu, Lake

Pollutant:	1,2,3-Trichloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155155, 1,2,3-Trichloropropane	Region 7
Havasu, Lake

LOE ID:

320387

Pollutant:

1,2,3-Trichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155040	Region 7
Havasu, Lake

Pollutant:	1,2,4-Trichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155040, 1,2,4-Trichlorobenzene	Region 7
Havasu, Lake

LOE ID:

321266

Pollutant:

1,2,4-Trichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155044	Region 7
Havasu, Lake

Pollutant:	1,2,4-Trimethylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155044, 1,2,4-Trimethylbenzene	Region 7
Havasu, Lake

LOE ID:

320290

Pollutant:

1,2,4-Trimethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155053	Region 7
Havasu, Lake

Pollutant:	1,2-Dibromo-3-chloropropane (DBCP)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155053, 1,2-Dibromo-3-chloropropane (DBCP)	Region 7
Havasu, Lake

LOE ID:

320388

Pollutant:

1,2-Dibromo-3-chloropropane (DBCP)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155056	Region 7
Havasu, Lake

Pollutant:	1,2-Dichloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed."

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155056, 1,2-Dichloroethane	Region 7
Havasu, Lake

LOE ID:

320080

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155056, 1,2-Dichloroethane	Region 7
Havasu, Lake

LOE ID:

319583

Pollutant:

1,2-Dichloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155128	Region 7
Havasu, Lake

Pollutant:	1,2-Dichloroethylene,-trans
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155128, 1,2-Dichloroethylene,-trans	Region 7
Havasu, Lake

LOE ID:

321267

Pollutant:

1,2-Dichloroethylene,-trans

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155062	Region 7
Havasu, Lake

Pollutant:	1,2-Dichloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155062, 1,2-Dichloropropane	Region 7
Havasu, Lake

LOE ID:

321268

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155062, 1,2-Dichloropropane	Region 7
Havasu, Lake

LOE ID:

320081

Pollutant:

1,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155147	Region 7
Havasu, Lake

Pollutant:	1,3,5-Trimethylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155147, 1,3,5-Trimethylbenzene	Region 7
Havasu, Lake

LOE ID:

320291

Pollutant:

1,3,5-Trimethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155156	Region 7
Havasu, Lake

Pollutant:	1,3-Dichloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155156, 1,3-Dichloropropane	Region 7
Havasu, Lake

LOE ID:

320389

Pollutant:

1,3-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155175	Region 7
Havasu, Lake

Pollutant:	1-Methylnaphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155175, 1-Methylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319891

Pollutant:

1-Methylnaphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155175, 1-Methylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319699

Pollutant:

1-Methylnaphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Acenaphthylene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155174	Region 7
Havasu, Lake

Pollutant:	1-Methylphenanthrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155174, 1-Methylphenanthrene	Region 7
Havasu, Lake

LOE ID:

319146

Pollutant:

1-Methylphenanthrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Phenanthrene, or 1-Methylphenanthrene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155157	Region 7
Havasu, Lake

Pollutant:	2,2-Dichloropropane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155157, 2,2-Dichloropropane	Region 7
Havasu, Lake

LOE ID:

320400

Pollutant:

2,2-Dichloropropane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155176	Region 7
Havasu, Lake

Pollutant:	2,3,5-Trimethylnaphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155176, 2,3,5-Trimethylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319700

Pollutant:

2,3,5-Trimethylnaphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155176, 2,3,5-Trimethylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319904

Pollutant:

2,3,5-Trimethylnaphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155177	Region 7
Havasu, Lake

Pollutant:	2,6-Dimethylnaphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155177, 2,6-Dimethylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319905

Pollutant:

2,6-Dimethylnaphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155177, 2,6-Dimethylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319701

Pollutant:

2,6-Dimethylnaphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155153	Region 7
Havasu, Lake

Pollutant:	2-Chlorotoluene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155153, 2-Chlorotoluene	Region 7
Havasu, Lake

LOE ID:

319501

Pollutant:

2-Chlorotoluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155206	Region 7
Havasu, Lake

Pollutant:	2-Hexanone
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155206, 2-Hexanone	Region 7
Havasu, Lake

LOE ID:

319797

Pollutant:

2-Hexanone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in May.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155120	Region 7
Havasu, Lake

Pollutant:	2-Methylnaphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155120, 2-Methylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319665

Pollutant:

2-Methylnaphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155120, 2-Methylnaphthalene	Region 7
Havasu, Lake

LOE ID:

319906

Pollutant:

2-Methylnaphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155154	Region 7
Havasu, Lake

Pollutant:	4-Chlorotoluene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155154, 4-Chlorotoluene	Region 7
Havasu, Lake

LOE ID:

319502

Pollutant:

4-Chlorotoluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155138	Region 7
Havasu, Lake

Pollutant:	Acenaphthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155138, Acenaphthene	Region 7
Havasu, Lake

LOE ID:

321171

Pollutant:

Acenaphthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 1200 ug/l Acenaphthene, 0.0093 ug/l alpha-BHC, 110 ug/l alpha-Endosulfan, 9600 ug/l Anthracene, 0.014 ug/l beta-BHC, 110 ug/l beta-Endosulfan, 680 ug/l Chlorobenzene, 1300 ug/l Copper, 2700 ug/l o-Dichlorobenzene, 400 ug/l m-Dichlorobenzene, 400 ug/l p-Dichlorobenzene, 110 ug/l Endosulfan Sulfate, 0.76 ug/l Endrin, 0.76 Endrin Aldehyde, 3100 ug/l Ethylbenzene, 300 ug/l Fluoranthene, 1300 ug/l Fluorene, 610 ug/l Nickel, 960 ug/l Pyrene,and 6800 ug/l Toluene (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155138, Acenaphthene	Region 7
Havasu, Lake

LOE ID:

319667

Pollutant:

Acenaphthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155139	Region 7
Havasu, Lake

Pollutant:	Acenaphthylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155139, Acenaphthylene	Region 7
Havasu, Lake

LOE ID:

319666

Pollutant:

Acenaphthylene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155139, Acenaphthylene	Region 7
Havasu, Lake

LOE ID:

319907

Pollutant:

Acenaphthylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155205	Region 7
Havasu, Lake

Pollutant:	Acetone
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155205, Acetone	Region 7
Havasu, Lake

LOE ID:

319798

Pollutant:

Acetone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in May.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155168	Region 7
Havasu, Lake

Pollutant:	Aldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

5566

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

Toxic Substances Monitoring Program (TSMP) Data for organic and inorganic chemicals in fish and sediment samples collected from water bodies located in the Colorado River Basin-Region 7. 1978-2000. State Water Resources Control Board. Sacramento, CA.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

319668

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

126484

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Aldrin. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, animal, or indigenous aquatic life. (Water Quality Control Plan for the Colorado River Basin Region)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Aldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

46155

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aldrin. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Survey. A Report of the Surface Water Ambient Monitoring Program (SWAMP). California State Water Resources Control Board, Sacramento, CA

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data for this line of evidence for Havasu, Lake was collected at 1 monitoring site [ Lake Havasu_BOG - 714PLH216]. Samples were collected from 1 location. Individual sample locations consisted of an area within a given waterbody from which fish tissue samples were collected. The number of sample locations per waterbody was based on the overall size of the waterbody (SWAMP, 2010). Specifics of individual sampling locations can be found in the supplemental report entitled "Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008" (SWAMP, 2008).

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Samples were collected, processed, and analyzed in accordance with the methods described in Quality Assurance Project Plan "Screening Study of Bioaccumulation in California Lakes and Reservoirs." (SWAMP, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

46154

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

126540

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155168, Aldrin	Region 7
Havasu, Lake

LOE ID:

320280

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses were used for the following constituents: 3 ug/l Aldrin, 0.22 ug/l alpha-Endosulfan, 340 ug/l Arsenic, 0.22 ug/l beta-Endosulfan, 2.4 ug/l Chlordane 1724 ug/l Chromium, 0.24 ug/l Dieldrin, 0.086 ug/l Endrin, 0.52 ug/l Heptachlor, and 0.52 Heptachlor Epoxide (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158740	Region 7
Havasu, Lake

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for conventional or other pollutants (Table 3.2 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158740, Alkalinity as CaCO3	Region 7
Havasu, Lake

LOE ID:

333792

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158740, Alkalinity as CaCO3	Region 7
Havasu, Lake

LOE ID:

333778

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158740, Alkalinity as CaCO3	Region 7
Havasu, Lake

LOE ID:

333791

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158740, Alkalinity as CaCO3	Region 7
Havasu, Lake

LOE ID:

333776

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158740, Alkalinity as CaCO3	Region 7
Havasu, Lake

LOE ID:

126681

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Alkalinity as CaCO3.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Alkalinity as CaCO3 criteria for the protection of freshwater aquatic life is 20000 ug/L (National Recommended Water Quality Criteria, 2009).

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	155214	Region 7
Havasu, Lake

Pollutant:	Aluminum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155214, Aluminum	Region 7
Havasu, Lake

LOE ID:

333795

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level incorporated by reference in the Water Quality Control Plan, Colorado River Basin Region for Aluminum is 1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155214, Aluminum	Region 7
Havasu, Lake

LOE ID:

333796

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The aluminum criterion for the protection of aquatic life, is pH, total hardness, and dissolved organic carbon (DOC) dependent. When total hardness or DOC data were not available, default values based on the level III ecoregions developed by U.S EPA were substituted (EPA, 2018). When pH data were not available, the median pH value for the ecoregion, a pH value from a comparable waterbody, or a pH value from a local study in the same waterbody was used as a comparable surrogate.

Guideline Reference:

Final Aquatic Life Ambient Water Quality Criteria for Aluminum. EPA-822-R-18-001. Washington, D.C.: Office of Water, USEPA.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155214, Aluminum	Region 7
Havasu, Lake

LOE ID:

333797

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Final Aquatic Life Ambient Water Quality Criteria for Aluminum. EPA-822-R-18-001. Washington, D.C.: Office of Water, USEPA.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155214, Aluminum	Region 7
Havasu, Lake

LOE ID:

321190

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155214, Aluminum	Region 7
Havasu, Lake

LOE ID:

320218

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used for the following constituents: 0.2 mg/l Aluminum, 500 mg/l Chloride, 1 mg/l Copper, 0.05 mg/l Manganese, 0.005 mg/l MTBE, 0.1 mg/l Silver, 500 mg/l Sulfate, 0.001 mg/l Thiobencarb, and 5 mg/l Zinc (CCR, title 22).

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155214, Aluminum	Region 7
Havasu, Lake

LOE ID:

319390

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Aluminum, Manganese, or Silver for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155196	Region 7
Havasu, Lake

Pollutant:	Ametryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155196, Ametryn	Region 7
Havasu, Lake

LOE ID:

319780

Pollutant:

Ametryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	169422	Region 7
Havasu, Lake

Pollutant:	Ammonia
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 169422, Ammonia	Region 7
Havasu, Lake

LOE ID:

333799

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for AmmoniaNAFreshwater 2013 document.

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2018-11-07 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 169422, Ammonia	Region 7
Havasu, Lake

LOE ID:

333803

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as 'the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure.'

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 169422, Ammonia	Region 7
Havasu, Lake

LOE ID:

333798

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2018-11-07 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155027	Region 7
Havasu, Lake

Pollutant:	Anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155027, Anthracene	Region 7
Havasu, Lake

LOE ID:

319356

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Anthracene, Benz(a)Anthracene, or Dibenzo(a,h)Anthracene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155027, Anthracene	Region 7
Havasu, Lake

LOE ID:

321172

Pollutant:

Anthracene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155028	Region 7
Havasu, Lake

Pollutant:	Antimony
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333821

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

319752

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples taken at 6 locations on the lake for Cadmium and Mercury. Thirty-five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. Thirty-four water quality samples from 5 locations for Nickel and Antimony were all acceptable. The 34 acceptable water quality samples were generally collected from 3/02/1995 through 1/28/2004 for Mercury and Cadmium, and 3/18/1997 through 1/28/2004 for Nickel and Antimony. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.006 mg/l Antimony, 0.005 mg/l Cadmium, 0.002 mg/l Mercury, and 0.1 mg/l Nickel (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Sixty-nine discrete samples were collected for Mercury and Cadmium, 34 for Nickel and Antimony. Samples were generally collected from 3/02/1995 through 1/28/2004 for Mercury and Cadmium, 3/18/1997 through 1/28/2004 for Nickel and Antimony. Samples were collected on 11 discrete dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998 , 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004 for Cadmium and Mercury. Samples were collected on 2 discrete dates in 1997, 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004 for Nickel and Antimony.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

319057

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Thirty-four water quality samples were taken at 5 locations on the lake, generally collected from 3/18/1997 through 1/28/2004. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 14 ug/l Antimony, and 610 ug/l Nickel (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Thirty-four discrete samples were collected. Samples were generally collected from 3/18/1997 through 1/28/2004. Samples were collected on 2 discrete dates in 1997, 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333819

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for antimony is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333823

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-11-15

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333832

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333812

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for antimony is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-11-15

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333814

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for antimony is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333828

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333827

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for antimony is 0.006 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333820

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-11-15

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333817

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333840

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155028, Antimony	Region 7
Havasu, Lake

LOE ID:

333807

Pollutant:

Antimony

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Antimony.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Quality Criteria for Water (Gold Book) states that for antimony toxicity to algae occurs at 610 ug/l. (USEPA, 1986)

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155029	Region 7
Havasu, Lake

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333865

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 150 ug/L. The conversion factor used to convert the total fraction criterion for arsenic to dissolved fraction criterion is 1. Therefore all data was considered to be representative of the dissolved fraction. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333851

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333853

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

126756

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

126817

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

126745

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

126815

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

126701

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

5138

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water quality samples were taken at 6 locations on the lake, generally collected from 3/02/1995 through 1/28/2004. Of these total samples , none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) of 340 ug/l for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Sixty-nine discrete samples were collected. Samples were generally collected from 3/02/1995 through 1/28/2004. Samples were collected on 11 discrete dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998 , 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

5171

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water quality samples were taken at 6 locations on the lake, generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the USFWS Biological Effects criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

United States Fish and Wildlife Service (USFWS) Bilogical Effects Criteria of 0.25 mg/l for the protection of aquatic life uses (USDOI, 1998).

Guideline Reference:

Guidelines for Interpretation of the Biological Effect of Selected Constituents in Biota, Water, and Sediment. US Department of Interior report.

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

126782

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Arsenic.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 150 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

321191

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

320281

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

319077

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected biannually in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the USFWS Biological Effect Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

United State Fish and Wildlife Service (USFWS) Biological Effect Criteria for the protection of aquatic life uses were used for the following constituents: 0.25 mg/l Arsenic, and 15 mg/l Copper (USFWS, 1998).

Guideline Reference:

Guidelines for Interpretation of the Biological Effect of Selected Constituents in Biota, Water, and Sediment. US Department of Interior report.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

319506

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water quality samples were taken at 6 locations on the lake, generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.050 mg/l Arsenic, 1 mg/l Barium, and 2 mg/l Fluoride (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

321026

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Consensus Based Sediment Quality Guideline Probable Effects Concentrations (PECs) for the protection of freshwater organisms to toxic effects were used for the following constituents: 33 mg/kg Arsenic, 1050 ug/kg Benz[a]anthrazene, 4.98 mg/kg Cadmium, 111 mg/kg Chromium, 1290 ug/kg Chrysene, 149 mg/kg Copper, 61.8 ug/g Dieldrin, 207 ug/kg Endrin, 2230 ug/kg Fluoranthene, 536 ug/kg Fluorene, 128 mg/kg Lead, 4.99 ug/kg Lindane/Hexachlorocyclohexane (HCH), 1.06 mg/kg Mercury, 561 ug/kg Naphthalene, 48.6 mg/kg Nickel, 1170 ug/kg Phenanthrene, 676 ug/kg PCBs (Polychlorinated biphenyls), and 1520 ug/kg Pyrene (Macdonald et al, 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333854

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333856

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333849

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333858

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for arsenic is 0.01 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155029, Arsenic	Region 7
Havasu, Lake

LOE ID:

333848

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155030	Region 7
Havasu, Lake

Pollutant:	Atrazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155030, Atrazine	Region 7
Havasu, Lake

LOE ID:

319074

Pollutant:

Atrazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155200	Region 7
Havasu, Lake

Pollutant:	Atroton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155200, Atroton	Region 7
Havasu, Lake

LOE ID:

319504

Pollutant:

Atroton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Atroton, Prometon, or Secbumeton for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155189	Region 7
Havasu, Lake

Pollutant:	Azinphos, Ethyl (Ethyl Guthion)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155189, Azinphos, Ethyl (Ethyl Guthion)	Region 7
Havasu, Lake

LOE ID:

319119

Pollutant:

Azinphos, Ethyl (Ethyl Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Azinphos, methyl, or Azinphos, ethyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155080	Region 7
Havasu, Lake

Pollutant:	Azinphos-methyl (Guthion)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155080, Azinphos-methyl (Guthion)	Region 7
Havasu, Lake

LOE ID:

319120

Pollutant:

Azinphos-methyl (Guthion)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Azinphos, methyl, or Azinphos, ethyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155032	Region 7
Havasu, Lake

Pollutant:	Barium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155032, Barium	Region 7
Havasu, Lake

LOE ID:

319507

Pollutant:

Barium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.050 mg/l Arsenic, 1 mg/l Barium, and 2 mg/l Fluoride (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155032, Barium	Region 7
Havasu, Lake

LOE ID:

333868

Pollutant:

Barium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Barium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for barium is 1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155032, Barium	Region 7
Havasu, Lake

LOE ID:

333869

Pollutant:

Barium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Barium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for barium is 1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155033	Region 7
Havasu, Lake

Pollutant:	Benzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s)

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155033, Benzene	Region 7
Havasu, Lake

LOE ID:

319584

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155033, Benzene	Region 7
Havasu, Lake

LOE ID:

5148

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 7 acceptable water quality samples were generally collected from 3/02/2000 through 7/05/2001. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria of 1.2 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155033, Benzene	Region 7
Havasu, Lake

LOE ID:

320094

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155033, Benzene	Region 7
Havasu, Lake

LOE ID:

319061

Pollutant:

Benzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 7 acceptable water quality samples were generally collected from 3/02/2000 through 7/5/2001. Of these total samples , none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.001 mg/l Benzene, 0.013 mg/l Methyl Tertiary-Butyl Ether (MTBE) (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155035	Region 7
Havasu, Lake

Pollutant:	Benzo(a)anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155035, Benzo(a)anthracene	Region 7
Havasu, Lake

LOE ID:

321114

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155035, Benzo(a)anthracene	Region 7
Havasu, Lake

LOE ID:

319357

Pollutant:

Benzo(a)anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Anthracene, Benz(a)Anthracene, or Dibenzo(a,h)Anthracene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155034	Region 7
Havasu, Lake

Pollutant:	Benzo(a)pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155034, Benzo(a)pyrene	Region 7
Havasu, Lake

LOE ID:

7622

Pollutant:

Benzo(a)pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Consensus Based Sediment Quality Guideline Probable Effects Concentration (PEC) of 1450 ug/kg for the protection of freshwater organisms to toxic effects (Macdonald et al, 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155034, Benzo(a)pyrene	Region 7
Havasu, Lake

LOE ID:

321199

Pollutant:

Benzo(a)pyrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155195	Region 7
Havasu, Lake

Pollutant:	Benzo(e)Pyrene (4,5-benzopyrene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155195, Benzo(e)Pyrene (4,5-benzopyrene)	Region 7
Havasu, Lake

LOE ID:

319765

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155195, Benzo(e)Pyrene (4,5-benzopyrene)	Region 7
Havasu, Lake

LOE ID:

319567

Pollutant:

Benzo(e)Pyrene (4,5-benzopyrene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155036	Region 7
Havasu, Lake

Pollutant:	Benzo[b]fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155036, Benzo[b]fluoranthene	Region 7
Havasu, Lake

LOE ID:

319217

Pollutant:

Benzo[b]fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Benzo(b)Fluoranthene, or Benzo(k)Fluoranthene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155037	Region 7
Havasu, Lake

Pollutant:	Benzo[g,h,i]perylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155037, Benzo[g,h,i]perylene	Region 7
Havasu, Lake

LOE ID:

319766

Pollutant:

Benzo[g,h,i]perylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155037, Benzo[g,h,i]perylene	Region 7
Havasu, Lake

LOE ID:

319358

Pollutant:

Benzo[g,h,i]perylene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155038	Region 7
Havasu, Lake

Pollutant:	Benzo[k]fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155038, Benzo[k]fluoranthene	Region 7
Havasu, Lake

LOE ID:

319218

Pollutant:

Benzo[k]fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Benzo(b)Fluoranthene, or Benzo(k)Fluoranthene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158725	Region 7
Havasu, Lake

Pollutant:	Beryllium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158725, Beryllium	Region 7
Havasu, Lake

LOE ID:

333872

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Beryllium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 ug/L.

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158725, Beryllium	Region 7
Havasu, Lake

LOE ID:

333873

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Beryllium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for beryllium is 0.004 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158725, Beryllium	Region 7
Havasu, Lake

LOE ID:

126847

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Beryllium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for beryllium is 0.004 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158725, Beryllium	Region 7
Havasu, Lake

LOE ID:

333881

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Beryllium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Gold Book states that beryllium chronic toxicity to freshwater aquatic life occur at concentrations as low as 5.3 ug/L.

Guideline Reference:

Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158725, Beryllium	Region 7
Havasu, Lake

LOE ID:

5158

Pollutant:

Beryllium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Forty-nine water samples were taken at 6 locations on the lake. Fifteen water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 34 acceptable water quality samples were generally collected from 5/15/1996 through 1/28/2004. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 0.004 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Forty-nine discrete samples were collected. Samples were generally collected from 5/15/1996 through 1/28/2004. Samples were collected on 8 discrete dates in 1996, 2 dates in 1997, 2 dates in 1998 , 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004. Water samples were generally collected and analyzed from 5/15/1996 through 1/28/2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155039	Region 7
Havasu, Lake

Pollutant:	Biphenyl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155039, Biphenyl	Region 7
Havasu, Lake

LOE ID:

319359

Pollutant:

Biphenyl

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, or Biphenyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155039, Biphenyl	Region 7
Havasu, Lake

LOE ID:

319778

Pollutant:

Biphenyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155169	Region 7
Havasu, Lake

Pollutant:	Bolstar
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155169, Bolstar	Region 7
Havasu, Lake

LOE ID:

320964

Pollutant:

Bolstar

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158726	Region 7
Havasu, Lake

Pollutant:	Boron
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

126810

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Boron.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The guideline for boron is 700 ug/L (0.7 mg/L).

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

126682

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Boron.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Drinking water notification levels are published by the Division of Drinking Water. Notification levels are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The notification level for Boron is 1 mg/L.

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

333894

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Boron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

333886

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Boron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

333889

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Boron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

333888

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Boron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

333892

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Boron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158726, Boron	Region 7
Havasu, Lake

LOE ID:

333887

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Boron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155151	Region 7
Havasu, Lake

Pollutant:	Bromobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155151, Bromobenzene	Region 7
Havasu, Lake

LOE ID:

320082

Pollutant:

Bromobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155152	Region 7
Havasu, Lake

Pollutant:	Bromochloromethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155152, Bromochloromethane	Region 7
Havasu, Lake

LOE ID:

320401

Pollutant:

Bromochloromethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155041	Region 7
Havasu, Lake

Pollutant:	Bromoform
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155041, Bromoform	Region 7
Havasu, Lake

LOE ID:

320091

Pollutant:

Bromoform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155042	Region 7
Havasu, Lake

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

321200

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

333907

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved cadmium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

319753

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.006 mg/l Antimony, 0.005 mg/l Cadmium, 0.002 mg/l Mercury, and 0.1 mg/l Nickel (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

319099

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples were taken at 6 locations on the lake for Cadmium. Thirty-five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. Thirty-four water quality samples from 5 locations for Nickel were all acceptable. The 34 acceptable water quality samples were generally collected from 3/02/1995 through 1/28/2004 for Cadmium, and 3/18/1997 through 1/28/2004 for Nickel. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses were used for the following constituents: The Hardness Dependent Concentrations of Cadmium and Nickel (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Sixty-nine discrete samples were collected for Mercury and Cadmium, 34 for Nickel. Samples were generally collected from 3/02/1995 through 1/28/2004 for Mercury and Cadmium, 3/18/1997 through 1/28/2004 for Nickel. Samples were collected on 11 discrete dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998 , 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004 for Cadmium and Mercury. Samples were collected on 2 discrete dates in 1997, 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004 for Nickel.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

319638

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the following limits: 10 ug/l Cadmium, 50 ug/l Lead, 4 ug/l Lindane/Hexachlorocyclohexane (HCH), 100 ug/l Methoxychlor, and 50 ug/l Silver (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

321115

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

333906

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

333915

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

333903

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

333905

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

333914

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

126821

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for cadmium in the Basin Plan is 0.005 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

7630

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Hardness Dependant Criterion Maximum Concentration (CMC) for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

126803

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155042, Cadmium	Region 7
Havasu, Lake

LOE ID:

126832

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Cadmium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	155043	Region 7
Havasu, Lake

Pollutant:	Carbon Tetrachloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155043, Carbon Tetrachloride	Region 7
Havasu, Lake

LOE ID:

319585

Pollutant:

Carbon Tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155043, Carbon Tetrachloride	Region 7
Havasu, Lake

LOE ID:

320092

Pollutant:

Carbon Tetrachloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155178	Region 7
Havasu, Lake

Pollutant:	Carbophenothion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155178, Carbophenothion	Region 7
Havasu, Lake

LOE ID:

320741

Pollutant:

Carbophenothion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155045	Region 7
Havasu, Lake

Pollutant:	Chlordane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

320965

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

5574

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

5447

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Fish Contaminant Goal (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 5.6 ug/kg to protect human health when consuming fish (OEHHA, 2008).

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

The field procedures are described in TSMP Data Reports and associated Appendices. CDFG's Laboratory applies a Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

126325

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

46128

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlordane, Total. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

46161

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for total chlordane in fish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

126319

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

46162

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

126318

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Total Chlordanes. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

321201

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155045, Chlordane	Region 7
Havasu, Lake

LOE ID:

320282

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155161	Region 7
Havasu, Lake

Pollutant:	Chlorfenvinphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155161, Chlorfenvinphos	Region 7
Havasu, Lake

LOE ID:

320415

Pollutant:

Chlorfenvinphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155046	Region 7
Havasu, Lake

Pollutant:	Chloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. The number of measured exceedances is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for conventional pollutants (Table 3.2 of the Listing Policy). Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that this water segment-pollutant combination should not be placed on the CWA section 303(d) List. Refer to the lines of evidence in this fact sheet for the data and information, sample counts and exceedances, quality assurance documentation, beneficial uses, and water quality objectives or numeric evaluation guidelines relied upon for this decision.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

126812

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Chloride.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Chloride criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 230000 ug/L (230 mg/L)(USEPA National Recommended Water Quality Criteria, 2006).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

333933

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

333921

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used: 500 mg/l Chloride (CCR, title 22).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

333937

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used: 500 mg/l Chloride (CCR, title 22).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

333931

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

333932

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

333926

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

126773

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Chloride.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance were used: 500 mg/l Chloride (CCR, title 22).

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

126694

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Chloride.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

319087

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water quality samples were taken at 6 locations on the lake, generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the CDPH SMCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155046, Chloride	Region 7
Havasu, Lake

LOE ID:

320219

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155047	Region 7
Havasu, Lake

Pollutant:	Chlorobenzene (mono)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155047, Chlorobenzene (mono)	Region 7
Havasu, Lake

LOE ID:

321209

Pollutant:

Chlorobenzene (mono)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155047, Chlorobenzene (mono)	Region 7
Havasu, Lake

LOE ID:

320990

Pollutant:

Chlorobenzene (mono)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155048	Region 7
Havasu, Lake

Pollutant:	Chloroethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155048, Chloroethane	Region 7
Havasu, Lake

LOE ID:

319865

Pollutant:

Chloroethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155049	Region 7
Havasu, Lake

Pollutant:	Chloroform
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155049, Chloroform	Region 7
Havasu, Lake

LOE ID:

320402

Pollutant:

Chloroform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158727	Region 7
Havasu, Lake

Pollutant:	Chlorophyll-a
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 158727, Chlorophyll-a	Region 7
Havasu, Lake

LOE ID:

333944

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Chlorophyll a.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Colorado River Basin, Chapter III, Section II).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

North Carolina Administrative code (NCAC), Title 15ANAEnvironmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158727, Chlorophyll-a	Region 7
Havasu, Lake

LOE ID:

333945

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Chlorophyll a.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155050	Region 7
Havasu, Lake

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155050, Chlorpyrifos	Region 7
Havasu, Lake

LOE ID:

5448

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 10000 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 155050, Chlorpyrifos	Region 7
Havasu, Lake

LOE ID:

319714

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155207	Region 7
Havasu, Lake

Pollutant:	Chlorpyrifos, methyl
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155207, Chlorpyrifos, methyl	Region 7
Havasu, Lake

LOE ID:

320416

Pollutant:

Chlorpyrifos, methyl

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155213	Region 7
Havasu, Lake

Pollutant:	Chromium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

319059

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples were taken at 6 locations on the lake. Thirty-four water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 35 acceptable water quality samples were generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.050 mg/l Chromium, and 0.050 mg/l Selenium (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

321116

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

333954

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

333952

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 180 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

333953

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 180 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

321210

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155213, Chromium	Region 7
Havasu, Lake

LOE ID:

320283

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158728	Region 7
Havasu, Lake

Pollutant:	Chromium, hexavalent
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158728, Chromium, hexavalent	Region 7
Havasu, Lake

LOE ID:

333956

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium VI.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 11 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158728, Chromium, hexavalent	Region 7
Havasu, Lake

LOE ID:

333957

Pollutant:

Chromium, hexavalent

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium VI.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (VI) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 11 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155051	Region 7
Havasu, Lake

Pollutant:	Chrysene (C1-C4)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155051, Chrysene (C1-C4)	Region 7
Havasu, Lake

LOE ID:

321125

Pollutant:

Chrysene (C1-C4)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155170	Region 7
Havasu, Lake

Pollutant:	Ciodrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155170, Ciodrin	Region 7
Havasu, Lake

LOE ID:

320966

Pollutant:

Ciodrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158729	Region 7
Havasu, Lake

Pollutant:	Cobalt
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 158729, Cobalt	Region 7
Havasu, Lake

LOE ID:

333958

Pollutant:

Cobalt

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Cobalt.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 0.05 mg/L criteria is the recommended maximum concentration of cobalt in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155054	Region 7
Havasu, Lake

Pollutant:	Copper
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. The number of measured exceedances is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicant pollutants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that this water segment-pollutant combination should not be placed on the CWA section 303(d) List. Refer to the lines of evidence in this fact sheet for the data and information, sample counts and exceedances, quality assurance documentation, beneficial uses, and water quality objectives or numeric evaluation guidelines relied upon for this decision.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

126837

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Copper.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site(s) (21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333976

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

126766

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality standard for Copper.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

126831

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Copper.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 2 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

7617

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the CTR Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Hardness Dependent Criterion Maximum Concentration (CMC) for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

126709

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality standard for Copper.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 2 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

5145

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples were taken at 6 locations on the lake. Twenty-seven water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 42 acceptable water quality samples were generally collected from 3/02/1995 through 1/28/2004 at 6 locations. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion of 1300 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

5168

Pollutant:

Copper

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples were taken at 6 locations on the lake. Twenty-seven water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 42 acceptable water quality samples were generally collected from 3/2/1995 through 1/8/2004 at 6 locations. Of these total samples, none exceeded the CDPH SMCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 1 mg/l for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

5139

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples were taken at 6 locations on the lake. Twenty-seven water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 42 acceptable water quality samples were generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Hardness Dependent Criterion Maximum Concentration (CMCs) for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

5172

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

United States Fish and Wildlife Service (USFWS) Bilogical Effects Criteria of 15 mg/l for the protection of aquatic life uses (USDOI, 1998).

Guideline Reference:

Guidelines for Interpretation of the Biological Effect of Selected Constituents in Biota, Water, and Sediment. US Department of Interior report.

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

320230

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

319078

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected biannually in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the USFWS Biological Effect Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Guidelines for Interpretation of the Biological Effect of Selected Constituents in Biota, Water, and Sediment. US Department of Interior report.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

321126

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333962

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 6 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333973

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333971

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333972

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333970

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333969

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-06-15 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155054, Copper	Region 7
Havasu, Lake

LOE ID:

333967

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 6 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155055	Region 7
Havasu, Lake

Pollutant:	Cumene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155055, Cumene	Region 7
Havasu, Lake

LOE ID:

320083

Pollutant:

Cumene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155162	Region 7
Havasu, Lake

Pollutant:	Cuomaphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155162, Cuomaphos	Region 7
Havasu, Lake

LOE ID:

320417

Pollutant:

Cuomaphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	170154	Region 7
Havasu, Lake

Pollutant:	DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

126653

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

7642

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) for pp'-DDT of 1.1 ug/l for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

46135

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

5449

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Fish Contaminant Goal (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 21 ug/kg to protect human health when consuming fish (OEHHA, 2008).

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

126650

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 1 of the 3 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite). Of these, 1 species (Channel Catfish) exceeded the water quality standard.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for total DDT in fish tissue is 15 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

46129

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

46134

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

126516

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170154, DDT (Dichlorodiphenyltrichloroethane)	Region 7
Havasu, Lake

LOE ID:

5582

Pollutant:

DDT (Dichlorodiphenyltrichloroethane)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 1000 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.


DECISION ID	155057	Region 7
Havasu, Lake

Pollutant:	Dacthal
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155057, Dacthal	Region 7
Havasu, Lake

LOE ID:

319551

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Dacthal, Mirex, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155057, Dacthal	Region 7
Havasu, Lake

LOE ID:

320967

Pollutant:

Dacthal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155059	Region 7
Havasu, Lake

Pollutant:	Demeton s
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155059, Demeton s	Region 7
Havasu, Lake

LOE ID:

320978

Pollutant:

Demeton s

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155060	Region 7
Havasu, Lake

Pollutant:	Diazinon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155060, Diazinon	Region 7
Havasu, Lake

LOE ID:

5450

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 300 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155060, Diazinon	Region 7
Havasu, Lake

LOE ID:

7620

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDFG Hazardous Assessment Criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Fish and Game (CDFG) Hazardous Assessment Criteria of 0.16 ug/l for the protection of aquatic life uses (Siepmann and Finlayson, 2000).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155060, Diazinon	Region 7
Havasu, Lake

LOE ID:

319715

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155061	Region 7
Havasu, Lake

Pollutant:	Dibenz[a,h]anthracene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155061, Dibenz[a,h]anthracene	Region 7
Havasu, Lake

LOE ID:

319374

Pollutant:

Dibenz[a,h]anthracene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Anthracene, Benz(a)Anthracene, or Dibenzo(a,h)Anthracene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155203	Region 7
Havasu, Lake

Pollutant:	Dibenzothiophene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155203, Dibenzothiophene	Region 7
Havasu, Lake

LOE ID:

319123

Pollutant:

Dibenzothiophene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Dibenzothiophene, or o-Xylene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155179	Region 7
Havasu, Lake

Pollutant:	Dichlofenthion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155179, Dichlofenthion	Region 7
Havasu, Lake

LOE ID:

320742

Pollutant:

Dichlofenthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155063	Region 7
Havasu, Lake

Pollutant:	Dichlorobenzophenone
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155063, Dichlorobenzophenone	Region 7
Havasu, Lake

LOE ID:

319221

Pollutant:

Dichlorobenzophenone

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Indeno(1,2,3,c,d)Pyrene, or pp'-Dichlorobenzophenone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155064	Region 7
Havasu, Lake

Pollutant:	Dichlorobromomethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155064, Dichlorobromomethane	Region 7
Havasu, Lake

LOE ID:

320093

Pollutant:

Dichlorobromomethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155065	Region 7
Havasu, Lake

Pollutant:	Dichlorodifluoromethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155065, Dichlorodifluoromethane	Region 7
Havasu, Lake

LOE ID:

319877

Pollutant:

Dichlorodifluoromethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155066	Region 7
Havasu, Lake

Pollutant:	Dichloromethane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155066, Dichloromethane	Region 7
Havasu, Lake

LOE ID:

319067

Pollutant:

Dichloromethane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 5/2002 at 1 location in the interior of the lake. This sample did not exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria for the protection of human health when consuming water and organisms from aquatic systems were used for the following constituents: 48 ug/l Methyl Bromide, and 5 ug/l Dichloromethane (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

A sample was collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water samples was collected. A water sample was collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155067	Region 7
Havasu, Lake

Pollutant:	Dichlorvos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155067, Dichlorvos	Region 7
Havasu, Lake

LOE ID:

320979

Pollutant:

Dichlorvos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155163	Region 7
Havasu, Lake

Pollutant:	Dicrotophos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155163, Dicrotophos	Region 7
Havasu, Lake

LOE ID:

320428

Pollutant:

Dicrotophos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155068	Region 7
Havasu, Lake

Pollutant:	Dieldrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

46142

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

126492

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Dieldrin. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

320284

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

321127

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

5592

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

46148

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

126290

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Dieldrin. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

46141

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Dieldrin. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155068, Dieldrin	Region 7
Havasu, Lake

LOE ID:

126298

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Dieldrin. Although data was collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite), all 3 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	155143	Region 7
Havasu, Lake

Pollutant:	Dimethoate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155143, Dimethoate	Region 7
Havasu, Lake

LOE ID:

320980

Pollutant:

Dimethoate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155209	Region 7
Havasu, Lake

Pollutant:	Dioxathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155209, Dioxathion	Region 7
Havasu, Lake

LOE ID:

320743

Pollutant:

Dioxathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155069	Region 7
Havasu, Lake

Pollutant:	Disulfoton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155069, Disulfoton	Region 7
Havasu, Lake

LOE ID:

320981

Pollutant:

Disulfoton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155070	Region 7
Havasu, Lake

Pollutant:	Dyfonate (Fonofos or Fonophos)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155070, Dyfonate (Fonofos or Fonophos)	Region 7
Havasu, Lake

LOE ID:

320429

Pollutant:

Dyfonate (Fonofos or Fonophos)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155071	Region 7
Havasu, Lake

Pollutant:	Endosulfan
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155071, Endosulfan	Region 7
Havasu, Lake

LOE ID:

319375

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Endosulfan 1, Endosulfan 2, or Endosulfan Sulfate for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155071, Endosulfan	Region 7
Havasu, Lake

LOE ID:

5601

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155071, Endosulfan	Region 7
Havasu, Lake

LOE ID:

5451

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 20,000 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155071, Endosulfan	Region 7
Havasu, Lake

LOE ID:

126329

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Endosulfan. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Endosulfan, Total concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155071, Endosulfan	Region 7
Havasu, Lake

LOE ID:

126621

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Endosulfan. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155071, Endosulfan	Region 7
Havasu, Lake

LOE ID:

126505

Pollutant:

Endosulfan

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Endosulfan. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	155072	Region 7
Havasu, Lake

Pollutant:	Endosulfan sulfate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155072, Endosulfan sulfate	Region 7
Havasu, Lake

LOE ID:

320991

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155073	Region 7
Havasu, Lake

Pollutant:	Endrin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

126328

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Endrin. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for endrin in fish tissue is 660 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; USEPA, 2000)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

46163

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Endrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

126414

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Endrin. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

5452

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 1000 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

46157

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

126536

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Endrin. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

46158

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

321136

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

320073

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

5608

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

Field procedures described in TSMP Data Reports and associated Appendices. Used CDFG's Laboratory Quality Assurance Program Plan procedures for laboratory Quality Assurance and Quality Control, as described in Rasmussen (1993).

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

321211

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155073, Endrin	Region 7
Havasu, Lake

LOE ID:

320992

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155171	Region 7
Havasu, Lake

Pollutant:	Endrin Ketone
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155171, Endrin Ketone	Region 7
Havasu, Lake

LOE ID:

320756

Pollutant:

Endrin Ketone

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155074	Region 7
Havasu, Lake

Pollutant:	Endrin aldehyde
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155074, Endrin aldehyde	Region 7
Havasu, Lake

LOE ID:

320993

Pollutant:

Endrin aldehyde

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155136	Region 7
Havasu, Lake

Pollutant:	Ethion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155136, Ethion	Region 7
Havasu, Lake

LOE ID:

5475

Pollutant:

Ethion

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 2000 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155136, Ethion	Region 7
Havasu, Lake

LOE ID:

320744

Pollutant:

Ethion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155145	Region 7
Havasu, Lake

Pollutant:	Ethoprop
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155145, Ethoprop	Region 7
Havasu, Lake

LOE ID:

320757

Pollutant:

Ethoprop

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155076	Region 7
Havasu, Lake

Pollutant:	Ethylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s)

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155076, Ethylbenzene	Region 7
Havasu, Lake

LOE ID:

321002

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155076, Ethylbenzene	Region 7
Havasu, Lake

LOE ID:

5163

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake, 8 water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 4 acceptable water quality samples were generally collected from 3/02/2000 through 7/5/2001. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 0.3 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 155076, Ethylbenzene	Region 7
Havasu, Lake

LOE ID:

5149

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Eight water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 4 acceptable water quality samples were generally collected from 3/02/2000 through 7/05/2001. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria of 3100 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155076, Ethylbenzene	Region 7
Havasu, Lake

LOE ID:

321219

Pollutant:

Ethylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155075	Region 7
Havasu, Lake

Pollutant:	Ethylene dibromide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155075, Ethylene dibromide	Region 7
Havasu, Lake

LOE ID:

320403

Pollutant:

Ethylene dibromide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155172	Region 7
Havasu, Lake

Pollutant:	Famphur
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155172, Famphur	Region 7
Havasu, Lake

LOE ID:

320758

Pollutant:

Famphur

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155164	Region 7
Havasu, Lake

Pollutant:	Fenchlorphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155164, Fenchlorphos	Region 7
Havasu, Lake

LOE ID:

320430

Pollutant:

Fenchlorphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155180	Region 7
Havasu, Lake

Pollutant:	Fenitrothion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155180, Fenitrothion	Region 7
Havasu, Lake

LOE ID:

320531

Pollutant:

Fenitrothion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155181	Region 7
Havasu, Lake

Pollutant:	Fensulfothion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155181, Fensulfothion	Region 7
Havasu, Lake

LOE ID:

320532

Pollutant:

Fensulfothion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155182	Region 7
Havasu, Lake

Pollutant:	Fenthion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155182, Fenthion	Region 7
Havasu, Lake

LOE ID:

320533

Pollutant:

Fenthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155077	Region 7
Havasu, Lake

Pollutant:	Fluoranthene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155077, Fluoranthene	Region 7
Havasu, Lake

LOE ID:

321036

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155077, Fluoranthene	Region 7
Havasu, Lake

LOE ID:

321137

Pollutant:

Fluoranthene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155078	Region 7
Havasu, Lake

Pollutant:	Fluorene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155078, Fluorene	Region 7
Havasu, Lake

LOE ID:

321037

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155078, Fluorene	Region 7
Havasu, Lake

LOE ID:

321138

Pollutant:

Fluorene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155079	Region 7
Havasu, Lake

Pollutant:	Fluoride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

333986

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fluoride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 1 mg/L criteria is the recommended maximum concentration of Fluoride in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

333983

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Fluoride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Primary Maximum Contaminant Level (MCL) for Fluoride, is 2 mg/l.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

319508

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.050 mg/l Arsenic, 1 mg/l Barium, and 2 mg/l Fluoride (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

126841

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Fluoride.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Primary Maximum Contaminant Level (MCL) for Fluoride, is 2 mg/l.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

126757

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Fluoride.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 1 mg/L criteria is the recommended maximum concentration of Fluoride in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

333988

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fluoride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. A 1 mg/L criteria is the recommended maximum concentration of Fluoride in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155079, Fluoride	Region 7
Havasu, Lake

LOE ID:

333982

Pollutant:

Fluoride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fluoride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Primary Maximum Contaminant Level (MCL) for Fluoride, is 2 mg/l.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155081	Region 7
Havasu, Lake

Pollutant:	Heptachlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). LOE Removal(s): 7675, 7633 ; LOE Replacement(s): 321220, 320074

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

321220

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

320074

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

126242

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Heptachlor. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

46377

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Heptachlor. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

46386

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

126230

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Heptachlor. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

5618

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155081, Heptachlor	Region 7
Havasu, Lake

LOE ID:

319219

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Heptachlor, or Heptachlor Epoxide for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155082	Region 7
Havasu, Lake

Pollutant:	Heptachlor epoxide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

321221

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

320075

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

319220

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Heptachlor, or Heptachlor Epoxide for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

5626

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

126367

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Heptachlor Epoxide. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor Epoxide concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

46396

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Heptachlor epoxide. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

126609

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Heptachlor Epoxide. Although data was collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite), all 3 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in fish tissue is 0.93 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 1999)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

46387

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

46395

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155082, Heptachlor epoxide	Region 7
Havasu, Lake

LOE ID:

126366

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Heptachlor Epoxide. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	155083	Region 7
Havasu, Lake

Pollutant:	Hexachlorobenzene/ HCB
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155083, Hexachlorobenzene/ HCB	Region 7
Havasu, Lake

LOE ID:

5453

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 20 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155083, Hexachlorobenzene/ HCB	Region 7
Havasu, Lake

LOE ID:

126463

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for Hexachlorobenzene. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in fish tissue is 2.8 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155083, Hexachlorobenzene/ HCB	Region 7
Havasu, Lake

LOE ID:

46404

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Hexachlorobenzene. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155083, Hexachlorobenzene/ HCB	Region 7
Havasu, Lake

LOE ID:

319639

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155083, Hexachlorobenzene/ HCB	Region 7
Havasu, Lake

LOE ID:

321229

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155084	Region 7
Havasu, Lake

Pollutant:	Hexachlorobutadiene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155084, Hexachlorobutadiene	Region 7
Havasu, Lake

LOE ID:

320105

Pollutant:

Hexachlorobutadiene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155086	Region 7
Havasu, Lake

Pollutant:	Indeno[1,2,3-cd]pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155086, Indeno[1,2,3-cd]pyrene	Region 7
Havasu, Lake

LOE ID:

319222

Pollutant:

Indeno[1,2,3-cd]pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Indeno(1,2,3,c,d)Pyrene, or pp'-Dichlorobenzophenone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155165	Region 7
Havasu, Lake

Pollutant:	Leptophos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155165, Leptophos	Region 7
Havasu, Lake

LOE ID:

320431

Pollutant:

Leptophos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155088	Region 7
Havasu, Lake

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

126181

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for HCH, gamma-. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Lindane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

126180

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for HCH, gamma-. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for lindane in fish tissue is 4.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

46164

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

321148

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

126182

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 3 samples exceeded the water quality standard for HCH, gamma-. Data were collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

5454

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Screening Value (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 30 ug/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

6735

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

319683

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

321230

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

46375

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155088, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 7
Havasu, Lake

LOE ID:

46376

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155089	Region 7
Havasu, Lake

Pollutant:	Malathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155089, Malathion	Region 7
Havasu, Lake

LOE ID:

320534

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155090	Region 7
Havasu, Lake

Pollutant:	Manganese
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. The number of measured exceedances is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicant pollutants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that this water segment-pollutant combination should not be placed on the CWA section 303(d) List. Refer to the lines of evidence in this fact sheet for the data and information, sample counts and exceedances, quality assurance documentation, beneficial uses, and water quality objectives or numeric evaluation guidelines relied upon for this decision.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

5133

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Thirrty-one water samples were taken at 3 locations on the lake. Seventeen water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 14 acceptable water quality samples were generally collected from 7/25/1995 through 1/27/2004. Of these total samples, none exceeded the CDPH SMCL (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 0.050 mg/l for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the north end (100100, 100101),and midlake (100099).

Temporal Representation:

Thirty-one discrete water samples were collected. Water samples were generally collected and analyzed from 3/3/1995 through 1/28/2004. Samples were collected on 8 discrete dates in 1995, 5 dates in 1996, 2 dates in 1997, 2 dates in 1998 , 2 dates in 2000, 6 dates in 2001, 2 dates in 2002, 2 dates in 2003, and 1 date in 2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods, similar to ADEQ, 2005. Sample analysis was carried out using USEPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

126743

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality standard for Manganese.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

334024

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Manganese.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

319391

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Aluminum, Manganese, or Silver for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

334019

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for Manganese.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

334026

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Manganese.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

334022

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Manganese.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-02-27

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

126699

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Manganese.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for manganese is 0.5 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155090, Manganese	Region 7
Havasu, Lake

LOE ID:

320231

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	170575	Region 7
Havasu, Lake

Pollutant:	Mercury
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 3.1, 3.5, and 3.6 of the Listing Policy. Under sections 3.1 and 3.5 a single line of evidence is necessary to assess listing status. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List Twenty-six lines of evidence are available in the administrative record to assess this pollutant. LOE 5160 was a multi-pollutant LOE and LOE 319767 replaces the assessment for those mercury data. LOE 7699 was a multi-pollutant LOE and LOE 321149 replaces the assessment for those mercury data. LOE Nos. 7676 and 7639 were reassessed using a different guideline. LOE 5547 is replaced with LOE 357762 due to reassessment of previous data due to adoption of the statewide mercury objectives. COMM (Sport fish objective) LOE 133130: 0 of 1 samples exceed the mercury objective and consist of 57 trophic level 4 fish. LOE 133121: 0 of 1 samples exceed the mercury objective and consist of 29 trophic level 3 fish. LOE 133297: 0 of 1 samples exceed the mercury objective and consist of 29 trophic level 3 fish. (CDFW legal limit) LOE 132889: 0 of 1 samples exceed the mercury objective and consist of 38 trophic level 4 fish. (CDFW legal limit) LOE 334333: 0 of 1 samples exceed the mercury objective and consist of 19 trophic level 4 fish. (CDFW legal limit) WILD (Sport fish objective) LOE 133015: 0 of 1 samples exceed the mercury objective and consist of 57 trophic level 4 fish. LOE 132999: 0 of 1 samples exceed the mercury objective and consist of 29 trophic level 3 fish. LOE 132888: 0 of 1 samples exceed the mercury objective and consist of 29 trophic level 3 fish. (CDFW legal limit) LOE 133316: 0 of 1 samples exceed the mercury objective and consist of 38 trophic level 4 fish. (CDFW legal limit) LOE 334370: 0 of 1 samples exceed the mercury objective and consist of 19 trophic level 4 fish. (CDFW legal limit) WILD (prey fish objective) LOE 132930: 0 of 1 samples exceed the mercury objective and consist of 10 prey fish. LOE 334372: 0 of 1 samples exceed the mercury objective and consist of 10 prey fish. LOE 357762: 0 of 1 samples exceed the mercury objective and consist of 5 prey fish Line of evidence No. 5131 received a Use Rating of Insufficient Information because of Poor Quality Assurance. In this LOE greater than 90 percent of the sample results could not be used because of the data quantitation requirements of section 6.1.5. The LOE contains 2 out of four samples that exceed the water quality objectives. These exceedances may result in a listing. However, most of the sample results could not be used because of poor QA. Had the quality of the data been better, these exceedances would not have resulted in a listing decision. In 2017 OEHHA released Health Advisory and Guidelines for Eating Fish from Lake Havasu (San Bernardino County). Fishing occurs at Lake Havasu and the fish species (Largemouth Bass) used for the assessments are part of 2017 Advisory.¿ Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the two dissolved water samples exceeded the drinking water MCL used to assess MUN beneficial use. Two of 40 total fraction water samples exceeded the California Toxics Rule criteria used to assess MUN beneficial use. 4. Tissue samples were compared with the sport fish objective and 0 of 2 CDFW legal limit samples exceed for WILD beneficial use and 0 of 2 CDFW legal limit samples exceed for the COMM beneficial use. The samples consist of trophic level 4 fish and are from a minimum of 2 annual averages and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 5. Tissue samples were compared with the prey fish objective and 0 of 3 samples exceed for WILD beneficial use. Samples may consist of a mix of trophic levels and are from a minimum of 3 annual averages and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 6. None of 2 sediment samples exceeded the sediment quality guidelines. 7. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:	Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the two dissolved water samples exceeded the drinking water MCL used to assess MUN beneficial use. Two of 40 total fraction water samples exceeded the California Toxics Rule criteria used to assess MUN beneficial use. 4. Tissue samples were compared with the sport fish objective and 0 of 2 CDFW legal limit samples exceed for WILD beneficial use and 0 of 2 CDFW legal limit samples exceed for the COMM beneficial use. The samples consist of trophic level 4 fish and are from a minimum of 2 annual averages and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 5. Tissue samples were compared with the prey fish objective and 0 of 3 samples exceed for WILD beneficial use. Samples may consist of a mix of trophic levels and are from a minimum of 3 annual averages and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 6. None of 2 sediment samples exceeded the sediment quality guidelines. 7. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

State Board Decision Recommendation:	Decision written by SWRCB staff.

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

321149

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

334032

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Mercury.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

334372

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Contamination in Lakes and Resrv data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of 1 sample exceeded the water quality threshold for Mercury. Monitors collected 3 composites: 1 composite of Bluegill composed of 10 fish, 1 composite of Largemouth Bass composed of 10 fish, and 1 composite of Threadfin Shad composed of 10 fish. All fish collected within the same calendar year with a reported length of 50-150 mm were averaged into a single sample, independent of species or trophic level, for comparison with the objective. All 30 fish were collected in a single calendar year, which resulted in 1 independent sample.

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Statewide Prey Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.05 mg/Kg wet weight whole fish samples of any fish species between 50 to 150 mm in total length collected between February 1 and July 31. (SWRCB Resolution No. 2017-0027)

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

Data for this line of evidence were collected between 2015-10-19 and 2015-10-19. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

334370

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Contamination in Lakes and Resrv data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of 1 sample exceeded the water quality threshold for Mercury. Monitors collected 19 composites of Largemouth Bass composed of 1 fish each. This LOE contains data only for trophic level 4 fish whose average length was inside the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations. Fish collected within the same calendar year were averaged into a single sample for comparison with the objective. All 19 fish were collected in a single calendar year, which resulted in 1 independent sample.

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. If trophic level 3 fish are used in the assessment then the Prey Fish Water Quality Objective must also be used to determine that the Sport Fish Objective is being met. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

Data for this line of evidence were collected between 2015-10-19 and 2015-10-21. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

334333

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Contamination in Lakes and Resrv data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of 1 sample exceeded the water quality threshold for Mercury. Monitors collected 19 composites of Largemouth Bass composed of 1 fish each. This LOE contains data only for trophic level 4 fish whose average length was inside the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations. Fish collected within the same calendar year were averaged into a single sample for comparison with the objective. All 19 fish were collected in a single calendar year, which resulted in 1 independent sample.

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of the Commercial and Sport Fishing beneficial comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

7676

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 5/2002 at 1 location in the interior of the lake. This sample did not exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 0.002 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

A sample was collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. A water sample was collected in 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

7653

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 5/2002 at 1 location in the interior of the lake. This sample did not exceed the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria of 0.050 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

A sample was collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. A water sample was collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

7639

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the NRWQC criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

National Recommended Water Quality Criteria (NRWQC) Criterion Maximum Concentration (CMC) of 1.4 ug/l for the protection of freshwater aquatic life uses (USEPA, 2002).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were usually collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

133297

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 29 fish were aggregated into 1 annual averages, which consisted of 4 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 2 composite(s) of Redear Sunfish each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 4 fish per composite, 1 composite(s) of Redear Sunfish each composed of 10 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

31103

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Fish were collected for tissue analysis at four locations from Lake Havasu. A total of 4 sample composites were generated from one species: Common Carp. Details of the compositing protocol can be found in the March 2009 report entitiled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). A total of 0 out of 4 samples exceeded the OHHEA fish tissue screening value for human health.

Data Reference:

Data associated with report entitled: Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Survey. A Report of the Surface Water Ambient Monitoring Program (SWAMP). California State Water Resources Control Board, Sacramento, CA

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Screening Value of 0.3 mg/kg to protect human health when consuming fish (OEHHA, 1999).

Guideline Reference:

Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment

Spatial Representation:

Samples were collected from four locations in Lake Havasu. As discussed in the Lakes and Reserviors Report (SWAMP, 2009), individual sample locations consisted of an area within a given waterbody with an approximate one-mile diameter, from which multiple fish tissue samples were collected. The number of sample locations per waterbody was based on the overall size of the waterbody. Specifics of individual sampling locations can be found in the supplemental report entitled "Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008" (SWAMP, 2008). Data collected from this waterbody was assigned under Station Name "Lake Havasu_BOG" in the SWAMP report.

Temporal Representation:

Samples were collected on 9/5/07 and 10/25/07

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

Samples were collected, processed, and analyzed in accordance with the methods described in "Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs." (SWAMP, 2008).

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

133130

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

133121

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 29 fish were aggregated into 1 annual averages, which consisted of 4 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 4 fish per composite, 2 composite(s) of Redear Sunfish each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 10 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

46405

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Mercury. Four composites (5 fish per composite) were generated from one species: common carp. These composites could not be used in the assessment due to total fish lengths for individual fish that do not fall within lengths noted in the guideline. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

The USEPA 304(a) recommended water quality criterion for concentrations of methylmercury in fish tissue of trophic level 4 fish (150 - 500 mm; fillet wet weight) is 0.20 mg/kg.

Guideline Reference:

Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001

Spatial Representation:

Data for this line of evidence for Havasu, Lake was collected at 1 monitoring site [ Lake Havasu_BOG - 714PLH216]. Samples were collected from 4 locations. Individual sample locations consisted of an area within a given waterbody from which fish tissue samples were collected. The number of sample locations per waterbody was based on the overall size of the waterbody (SWAMP, 2010). Specifics of individual sampling locations can be found in the supplemental report entitled "Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008" (SWAMP, 2008).

Temporal Representation:

Data was collected over the time period 9/5/2007-10/25/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

132889

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 38 fish were aggregated into 1 annual averages, which consisted of 2 fish species (32 composite(s) of Largemouth Bass each composed of 1 fish per composite, 6 composite(s) of Striped Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

133316

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 4 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 38 fish were aggregated into 1 annual averages, which consisted of 2 fish species (32 composite(s) of Largemouth Bass each composed of 1 fish per composite, 6 composite(s) of Striped Bass each composed of 1 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

132888

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. This LOE contains data only for trophic level 3 fish. The concentration of Mercury in fish collected within the same calendar year, for the same trophic level were averaged into a single sample for comparison with the objective. A total of 29 fish were aggregated into 1 annual averages, which consisted of 4 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 4 fish per composite, 2 composite(s) of Redear Sunfish each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 10 fish per composite). This LOE does not contain data from fish whos average length was outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

132999

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

132930

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. All fish collected within the same calendar year with a reported length of 50-150 mm were averaged into a single sample, independent of species or trophic level, for comparison with the objective. This LOE consists of a total of 10 fish, which were aggregated into 1 annual averages, consisting of 1 fish species (2 composite(s) of Bluegill each composed of 5 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-11 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

133015

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-11

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

357762

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Toxic Substances Monitoring Program data for Havasu, Lake to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality standard for Mercury. All fish collected within the same calendar year with a reported length of 50-150 mm were averaged into a single sample, independent of species or trophic level, for comparison with the objective. This LOE consists of a total of 5 fish, which were aggregated into 1 annual averages, consisting of 1 fish species (1 composite(s) of Bluegill each composed of 5 fish per composite).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): Lake Havasu.

Temporal Representation:

Data for this line of evidence were collected between 1987-10-20 and 1987-10-20

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

126776

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Mercury.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

5131

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-seven water samples were taken at 3 locations on the lake. Sixty-three water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The four acceptable water quality samples were collected on 2/07/2001, and 11/28/2001 at 3 locations in the lake. Of these total samples, 2 exceeded the CTR Criteria. The exceedences were found in samples collected on 11/28/2001 from the two midlake locations 100102 and 100099) (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria of 0.050 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), and midlake (100102 and 100099).

Temporal Representation:

Sixty-seven water samples were collected. Water samples were generally collected and analyzed from 3/2/1995 through 1/8/2004.Samples were collected on 10 discrete dates in 1995, 8 dates in 1996, 2 dates in 1997, 2 dates in 1998 , 3 dates in 2000, 8 dates in 2001, and 2 dates each in 2002, 2003, and 2004. The exceedences were found in samples collected on 11/28/2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods, similar to ADEQ, 2005. Sample analysis was carried out using USEPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

26717

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-nine water samples were taken at 6 locations on the lake. Thirty-five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 34 acceptable water quality samples were generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the NRWQC criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

National Recommended Water Quality Criteria (NRWQC) Criterion Maximum Concentration (CMC) of 1.4 ug/l for the protection of freshwater aquatic life uses (USEPA, 2002).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

334030

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Mercury.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentration (4-day average concentrations) for freshwater aquatic organisms exposure to total mercury is 0.77 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

334031

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Mercury.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The mercury criteria for the protection of human health from the consumption of water and organisms for mercury is 0.050 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 170575, Mercury	Region 7
Havasu, Lake

LOE ID:

319767

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.006 mg/l Antimony, 0.005 mg/l Cadmium, 0.002 mg/l Mercury, and 0.1 mg/l Nickel (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155166	Region 7
Havasu, Lake

Pollutant:	Merphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155166, Merphos	Region 7
Havasu, Lake

LOE ID:

320326

Pollutant:

Merphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155141	Region 7
Havasu, Lake

Pollutant:	Methidathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155141, Methidathion	Region 7
Havasu, Lake

LOE ID:

320545

Pollutant:

Methidathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155092	Region 7
Havasu, Lake

Pollutant:	Methoxychlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). LOE Removal(s): 29540, 7692, 7675; LOE Replacement(s): 319640, 319684, 321231

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155092, Methoxychlor	Region 7
Havasu, Lake

LOE ID:

7627

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the USEPA criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

USEPA Drinking Water Criteria of 40 ug/l for the protection of drinking water uses (USEPA, 2002).

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155092, Methoxychlor	Region 7
Havasu, Lake

LOE ID:

319640

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155092, Methoxychlor	Region 7
Havasu, Lake

LOE ID:

321231

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155092, Methoxychlor	Region 7
Havasu, Lake

LOE ID:

319684

Pollutant:

Methoxychlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155097	Region 7
Havasu, Lake

Pollutant:	Methyl Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155097, Methyl Parathion	Region 7
Havasu, Lake

LOE ID:

319132

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Parathion, or Methyl Parathion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155097, Methyl Parathion	Region 7
Havasu, Lake

LOE ID:

320542

Pollutant:

Methyl Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155098	Region 7
Havasu, Lake

Pollutant:	Methyl Tertiary-Butyl Ether (MTBE)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155098, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Havasu, Lake

LOE ID:

5170

Pollutant:

Methyl Tertiary-Butyl Ether (MTBE)

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 7 acceptable water quality samples were generally collected from 3/02/2000 through 7/5/2001. Of these total samples, none exceeded the CDPH SMCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 0.005 mg/l for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155098, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Havasu, Lake

LOE ID:

320232

Pollutant:

Methyl Tertiary-Butyl Ether (MTBE)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155098, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Havasu, Lake

LOE ID:

321239

Pollutant:

Methyl Tertiary-Butyl Ether (MTBE)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155098, Methyl Tertiary-Butyl Ether (MTBE)	Region 7
Havasu, Lake

LOE ID:

319086

Pollutant:

Methyl Tertiary-Butyl Ether (MTBE)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Five water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 7 acceptable water quality samples were generally collected from 3/02/2000 through 7/5/2001. Of these total samples , none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.001 mg/l Benzene, 0.013 mg/l Methyl Tertiary-Butyl Ether (MTBE) (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155093	Region 7
Havasu, Lake

Pollutant:	Methyl bromide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155093, Methyl bromide	Region 7
Havasu, Lake

LOE ID:

319068

Pollutant:

Methyl bromide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 5/2002 at 1 location in the interior of the lake. This sample did not exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

A sample was collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water samples was collected. A water sample was collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155094	Region 7
Havasu, Lake

Pollutant:	Methyl chloride (Chloromethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155094, Methyl chloride (Chloromethane)	Region 7
Havasu, Lake

LOE ID:

319878

Pollutant:

Methyl chloride (Chloromethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155095	Region 7
Havasu, Lake

Pollutant:	Methyl ethyl ketone (2-Butanone)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155095, Methyl ethyl ketone (2-Butanone)	Region 7
Havasu, Lake

LOE ID:

319799

Pollutant:

Methyl ethyl ketone (2-Butanone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in May.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155096	Region 7
Havasu, Lake

Pollutant:	Methyl isobutyl ketone (Methyl-2-Pentanone)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155096, Methyl isobutyl ketone (Methyl-2-Pentanone)	Region 7
Havasu, Lake

LOE ID:

319800

Pollutant:

Methyl isobutyl ketone (Methyl-2-Pentanone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acetone, Methyl Isobutyl Ketone, Methyl Ethyl Ketone, or 2-Hexanone for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in May.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155099	Region 7
Havasu, Lake

Pollutant:	Methylene bromide (Dibromomethane)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155099, Methylene bromide (Dibromomethane)	Region 7
Havasu, Lake

LOE ID:

320414

Pollutant:

Methylene bromide (Dibromomethane)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155167	Region 7
Havasu, Lake

Pollutant:	Mevinphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155167, Mevinphos	Region 7
Havasu, Lake

LOE ID:

320327

Pollutant:

Mevinphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155100	Region 7
Havasu, Lake

Pollutant:	Mirex
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155100, Mirex	Region 7
Havasu, Lake

LOE ID:

46412

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Mirex. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for mirex in fish tissue is 0.28 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155100, Mirex	Region 7
Havasu, Lake

LOE ID:

319552

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Dacthal, Mirex, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155100, Mirex	Region 7
Havasu, Lake

LOE ID:

320759

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155100, Mirex	Region 7
Havasu, Lake

LOE ID:

126324

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Mirex. Although data was collected for 3 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite, 1 composite(s) of Largemouth Bass each composed of 20 fish per composite, 1 composite(s) of Striped Bass each composed of 20 fish per composite), all 3 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for mirex in fish tissue is 0.28 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008; OEHHA, 1992)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	155101	Region 7
Havasu, Lake

Pollutant:	Molinate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155101, Molinate	Region 7
Havasu, Lake

LOE ID:

321240

Pollutant:

Molinate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158731	Region 7
Havasu, Lake

Pollutant:	Molybdenum
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

334048

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Molybdenum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

EPA Drinking Water Lifetime Health advisory level for Molybdenum is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

334051

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Molybdenum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The recommended maximum concentration of molybdenum in irrigation water is 0.01 mg/L.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

334047

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Molybdenum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The recommended maximum concentration of molybdenum in irrigation water is 0.01 mg/L.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

334044

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Molybdenum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The recommended maximum concentration of molybdenum in irrigation water is 0.01 mg/L.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

126783

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Molybdenum.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The 0.01 mg/L criteria is the recommended maximum concentration of molybdenum in irrigation water.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

126717

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Molybdenum.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

EPA Drinking Water Lifetime Health advisory level for Molybdenum is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

334045

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Molybdenum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

EPA Drinking Water Lifetime Health advisory level for Molybdenum is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158731, Molybdenum	Region 7
Havasu, Lake

LOE ID:

334049

Pollutant:

Molybdenum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Molybdenum.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

EPA Drinking Water Lifetime Health advisory level for Molybdenum is 0.04 mg/L.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155173	Region 7
Havasu, Lake

Pollutant:	Naled
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155173, Naled	Region 7
Havasu, Lake

LOE ID:

320772

Pollutant:

Naled

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155102	Region 7
Havasu, Lake

Pollutant:	Naphthalene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155102, Naphthalene	Region 7
Havasu, Lake

LOE ID:

319920

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Acenaphthylene, Naphthalene, 1-Methylnaphthalene, 2-Methynaphthalene, 2,6-Dimethylnaphthalene, or 2,3,5-Trimethylnaphthalene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155102, Naphthalene	Region 7
Havasu, Lake

LOE ID:

321158

Pollutant:

Naphthalene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155103	Region 7
Havasu, Lake

Pollutant:	Nickel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

334059

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved nickel criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

319058

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Thirty-four water quality samples were taken at 5 locations on the lake, generally collected from 3/18/1997 through 1/28/2004. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

319056

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

321038

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

321241

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

334052

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

334057

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2018-04-18 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

321159

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

319787

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR hardness dependent criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Hardness Dependent Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses were used for the following constituents: Lead,Nickel, Silver, and Zinc (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

334053

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155103, Nickel	Region 7
Havasu, Lake

LOE ID:

319768

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.006 mg/l Antimony, 0.005 mg/l Cadmium, 0.002 mg/l Mercury, and 0.1 mg/l Nickel (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	70718	Region 7
Havasu, Lake

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of 75 samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 75 water samples exceeded the drinking water MCL. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 70718, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 7
Havasu, Lake

LOE ID:

5156

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Seventy water quality samples were taken at 6 locations on the lake, generally collected from 3/02/1995 through 1/28/2004. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 10 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Seventy discrete samples were collected. Samples were generally collected from 3/02/1995 through 1/28/2004. Samples were collected on 11 discrete dates in 1995, 9 dates in 1996, 4 dates in 1997, 2 dates in 1998, 2 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 2 dates in 2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 70718, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 7
Havasu, Lake

LOE ID:

126796

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Nitrate + Nitrite as N.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	169695	Region 7
Havasu, Lake

Pollutant:	Nitrogen, Nitrate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with updated database requirements. Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 169695, Nitrogen, Nitrate	Region 7
Havasu, Lake

LOE ID:

321249

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	169941	Region 7
Havasu, Lake

Pollutant:	Nitrogen, Nitrite
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 169941, Nitrogen, Nitrite	Region 7
Havasu, Lake

LOE ID:

321250

Pollutant:

Nitrogen, Nitrite

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155105	Region 7
Havasu, Lake

Pollutant:	Oxadiazon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155105, Oxadiazon	Region 7
Havasu, Lake

LOE ID:

319553

Pollutant:

Oxadiazon

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Dacthal, Mirex, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155105, Oxadiazon	Region 7
Havasu, Lake

LOE ID:

320924

Pollutant:

Oxadiazon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlordane, Bolstar, Ciodrin, Dacthal, Demeton s, Dichlorvos, Dimethoate, Disulfoton, Endrin Ketone, Ethoprop, Famphur, Mirex, Naled, or Oxadiazon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155190	Region 7
Havasu, Lake

Pollutant:	Oxychlordane
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155190, Oxychlordane	Region 7
Havasu, Lake

LOE ID:

319568

Pollutant:

Oxychlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Oxychlordane, Perylene, or Tedion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155190, Oxychlordane	Region 7
Havasu, Lake

LOE ID:

320329

Pollutant:

Oxychlordane

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155112	Region 7
Havasu, Lake

Pollutant:	PCBs (Polychlorinated biphenyls)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

46420

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for PCB, Total. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). Total PCB was assessed for as follows: PCB aroclors and congeners were summed separately and the sum that yielded the highest value was used for the assessment.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total PCB concentration of 500 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

46421

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

321160

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

321251

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

5638

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 500 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

126630

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 1 samples exceeded the water quality standard for PCBs (Polychlorinated biphenyls). Data were collected for 1 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

126631

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

46413

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for polychlorinated biphenyls in fish tissue is 2.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155112, PCBs (Polychlorinated biphenyls)	Region 7
Havasu, Lake

LOE ID:

126586

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 1 of the 1 samples exceeded the water quality standard for PCBs (Polychlorinated biphenyls). Data were collected for 1 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite). Of these, 1 species (Channel Catfish) exceeded the water quality standard.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	155108	Region 7
Havasu, Lake

Pollutant:	Parathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155108, Parathion	Region 7
Havasu, Lake

LOE ID:

320543

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155108, Parathion	Region 7
Havasu, Lake

LOE ID:

319133

Pollutant:

Parathion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Parathion, or Methyl Parathion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155191	Region 7
Havasu, Lake

Pollutant:	Perylene (Dibenz(de,kl)anthracene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155191, Perylene (Dibenz(de,kl)anthracene)	Region 7
Havasu, Lake

LOE ID:

319569

Pollutant:

Perylene (Dibenz(de,kl)anthracene)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Oxychlordane, Perylene, or Tedion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155191, Perylene (Dibenz(de,kl)anthracene)	Region 7
Havasu, Lake

LOE ID:

320344

Pollutant:

Perylene (Dibenz(de,kl)anthracene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155111	Region 7
Havasu, Lake

Pollutant:	Phenanthrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155111, Phenanthrene	Region 7
Havasu, Lake

LOE ID:

321169

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155111, Phenanthrene	Region 7
Havasu, Lake

LOE ID:

319116

Pollutant:

Phenanthrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Phenanthrene, or 1-Methylphenanthrene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155146	Region 7
Havasu, Lake

Pollutant:	Phorate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155146, Phorate	Region 7
Havasu, Lake

LOE ID:

320345

Pollutant:

Phorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155183	Region 7
Havasu, Lake

Pollutant:	Phosmet
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155183, Phosmet	Region 7
Havasu, Lake

LOE ID:

320342

Pollutant:

Phosmet

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155184	Region 7
Havasu, Lake

Pollutant:	Phosphamidon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155184, Phosphamidon	Region 7
Havasu, Lake

LOE ID:

320343

Pollutant:

Phosphamidon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155113	Region 7
Havasu, Lake

Pollutant:	Prometon (Prometone)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155113, Prometon (Prometone)	Region 7
Havasu, Lake

LOE ID:

319517

Pollutant:

Prometon (Prometone)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Atroton, Prometon, or Secbumeton for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155142	Region 7
Havasu, Lake

Pollutant:	Prometryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155142, Prometryn	Region 7
Havasu, Lake

LOE ID:

319781

Pollutant:

Prometryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155201	Region 7
Havasu, Lake

Pollutant:	Propazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155201, Propazine	Region 7
Havasu, Lake

LOE ID:

319121

Pollutant:

Propazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Propazine, or Terbuthylazine for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155114	Region 7
Havasu, Lake

Pollutant:	Pyrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155114, Pyrene	Region 7
Havasu, Lake

LOE ID:

321039

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155114, Pyrene	Region 7
Havasu, Lake

LOE ID:

321170

Pollutant:

Pyrene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155199	Region 7
Havasu, Lake

Pollutant:	Secbumeton
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155199, Secbumeton	Region 7
Havasu, Lake

LOE ID:

319518

Pollutant:

Secbumeton

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Atroton, Prometon, or Secbumeton for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155115	Region 7
Havasu, Lake

Pollutant:	Selenium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

46429

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Selenium. Four composites (5 fish per composite) were generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

The OEHHA Fish Contaminant Goal for selenium in fish tissue is 7.4 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A background dietary consumption rate of 0.114 mg/day is applied for this micronutrient.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected over the time period 9/5/2007-10/25/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

126263

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows 0 of the 8 samples exceeded the water quality standard for Selenium. Data were collected for 8 fish species (1 composite(s) of Channel Catfish each composed of 5 fish per composite, 1 composite(s) of Largemouth Bass each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 4 fish per composite, 3 composite(s) of Bluegill each composed of 5 fish per composite, 1 composite(s) of Redear Sunfish each composed of 10 fish per composite, 2 composite(s) of Redear Sunfish each composed of 5 fish per composite, 30 composite(s) of Striped Bass each composed of 1 fish per composite, 5 composite(s) of Tilapia spp. each composed of 1 fish per composite).

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

30276

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of Selenium for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

5455

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the OEHHA Fish Contaminant Goal (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Office of Environmental Health Hazard Assessment (OEHHA) Fish Contaminant Goal of 7400 ug/kg to protect human health when consuming fish (OEHHA, 2008).

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

126754

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Selenium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

126688

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Selenium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

5176

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified below¿Selenium 0.01 mg/l (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

126824

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Selenium.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

321259

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

319060

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.050 mg/l Chromium, and 0.050 mg/l Selenium (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334195

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334205

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334200

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334206

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334198

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334202

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334199

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334193

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155115, Selenium	Region 7
Havasu, Lake

LOE ID:

334196

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155116	Region 7
Havasu, Lake

Pollutant:	Silver
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

319062

Pollutant:

Silver

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

319681

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

320233

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

319801

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR hardness dependent criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

319388

Pollutant:

Silver

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Aluminum, Manganese, or Silver for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

319097

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Hardness Dependent Criterion Maximum Concentrations (CMCs) for the protection of freshwater aquatic life uses were used for the following constituents: Silver, and Zinc (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155116, Silver	Region 7
Havasu, Lake

LOE ID:

5175

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155117	Region 7
Havasu, Lake

Pollutant:	Simazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155117, Simazine	Region 7
Havasu, Lake

LOE ID:

319075

Pollutant:

Simazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155197	Region 7
Havasu, Lake

Pollutant:	Simetryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155197, Simetryn	Region 7
Havasu, Lake

LOE ID:

319782

Pollutant:

Simetryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158734	Region 7
Havasu, Lake

Pollutant:	Sodium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2020)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollution

Regional Board Conclusion:	This decision was updated by Regional Board staff with assessment of data using the flow-weighted site-specific salinity objective for the Colorado River. This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Lines of Evidence (LOEs) 126820 and 126753 were replaced with LOE 198743, in which flow-weighted data was assessed with the flow-weighted objective in the Basin Plan. One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the thirty-nine (39) samples exceeded the water quality objective(s). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero (0) of the thirty-nine (39) samples exceed the site specific water quality objective(s) in Basin Plan. This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

336268

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Sodium.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

334221

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for Sodium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

334223

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 14 of 14 samples exceeded the water quality threshold for Sodium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

334214

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 14 of 14 samples exceeded the water quality threshold for Sodium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

334215

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for Sodium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

336267

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Sodium.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158734, Sodium	Region 7
Havasu, Lake

LOE ID:

198743

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data associated with the Quality Of Water Colorado River Basin Progress Report No. 25 (U.S. Department of the Interior, Bureau of Reclamation, Upper Colorado Region, 2017), to determine beneficial use support and results are as follows: 0 of 39 samples exceeded the water quality standard.

Data Reference:

Quality Of Water Colorado River Basin Progress Report No. 25

Data Associated with Quality Of Water Colorado River Basin Progress Report No. 25

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Because Sodium is a component of TDS, and since the Colorado River and associated lakes such as Lake Havasu have site specific water quality objectives for salinity expressed as TDS, it is more appropriate to treat the Sodium assessment for Lake Havasu similar to the assessment for TDS in making any listing decisions.

Colorado River Basin Region Water Quality Control Plan includes the following Salinity/TDS objectives for the Colorado River above and below Imperial Dam: Colorado River (Above Imperial Dam) - The Seven States Colorado River Salinity Control Forum developed water quality standards in 1975 for salinity. The flow-weighted average annual numeric criteria for salinity (total dissolved solids) were established at three locations on the lower Colorado River: 1) Below Hoover Dam AZ-NV, 723 mg/l; 2) Below Parker Dam AZ-CA, 747 mg/l; 3) Imperial Dam AZ-CA, 879 mg/l. (CRBRWQCB, 1/18/2019)

Colorado River (Below Imperial Dam) – Below Imperial Dam, the River's salinity will be controlled to meet the terms of the agreement with Mexico on salinity in Minute No. 242 of the International Boundary and Water Commission, entitled "Permanent and Definitive Solution to the International Problem of the Salinity of the Colorado River". This agreement states that measures will be taken to assure that the waters delivered to Mexico upstream from Morelos Dam will have annual average salinity concentration of no more than 115 ppm (+ 30 ppm) total dissolved solids greater than the annual average salinity
concentration of Colorado River water arriving at Imperial Dam. Title I of
Public Law 93-320 is the legislation which implements the provisions of Minute No. 242. Minute No. 242 and Title I constitute a federal numeric criterion and plan of implementation for the River below Imperial Dam. (CRBRWQCB, 1/18/2019)

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Objective/Criterion Reference:

Response to Comments, Clean Water Act Sections 305(b) and 303(d) 2018 Draft Integrated Report for the Colorado River Basin Region, CRBRWQCB, November 2019)

Objective/Criterion Reference:

Minute 242: Permanent and Definitive Solution to the International Problem of the Salinity of the Colorado River

Objective/Criterion Reference:

Water Quality Standards for Salinity Including Numeric Criteria and Plan of Implementation for Salinity Control Colorado River System.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) 09427520 Colorado River below Parker Dam, AZ-CA, 09429490 Colorado River above Imperial Dam, AZ-CA, 09421500 Colorado River below Hoover Dam, AZ-NV (Out of state, upgradient, data used reviewed)

Temporal Representation:

The samples were collected between the dates of 1975 and 2013.

Environmental Conditions:

QAPP Information:

USGS/Bureau of Reclamation Data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	158735	Region 7
Havasu, Lake

Pollutant:	Strontium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 158735, Strontium	Region 7
Havasu, Lake

LOE ID:

334241

Pollutant:

Strontium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Strontium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Stronitum as a drinking water level is a concentration of 4 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155118	Region 7
Havasu, Lake

Pollutant:	Styrene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155118, Styrene	Region 7
Havasu, Lake

LOE ID:

319082

Pollutant:

Styrene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 5/2002 at 1 location in the interior of the lake. This sample did not exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.1 mg/l Styrene, and 0.15 mg/l Trichlorofluoromethane (CFC-11) (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Sample was collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. A water sample was collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155119	Region 7
Havasu, Lake

Pollutant:	Sulfates
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the samples exceed the threshold. and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155119, Sulfates	Region 7
Havasu, Lake

LOE ID:

126774

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for Sulfate.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance of 500 mg/l.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155119, Sulfates	Region 7
Havasu, Lake

LOE ID:

319088

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155119, Sulfates	Region 7
Havasu, Lake

LOE ID:

320244

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155119, Sulfates	Region 7
Havasu, Lake

LOE ID:

334243

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Sulfate.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance of 500 mg/l.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155119, Sulfates	Region 7
Havasu, Lake

LOE ID:

334246

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceeded the water quality threshold for Sulfate.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The Drinking Water Secondary Maximum Contaminant Levels (SMCLs) for consumer acceptance of 500 mg/l.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-04-03

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155185	Region 7
Havasu, Lake

Pollutant:	Sulfotep
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155185, Sulfotep	Region 7
Havasu, Lake

LOE ID:

320361

Pollutant:

Sulfotep

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155192	Region 7
Havasu, Lake

Pollutant:	Tedion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155192, Tedion	Region 7
Havasu, Lake

LOE ID:

319566

Pollutant:

Tedion

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Oxychlordane, Perylene, or Tedion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155192, Tedion	Region 7
Havasu, Lake

LOE ID:

320362

Pollutant:

Tedion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158736	Region 7
Havasu, Lake

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	3 lines of evidence are available in the administrative record to assess this pollutant. 12 of the 25 samples exceed the evaluation guideline. This surpasses the minimum number of measured exceedances needed to place a water segment on the section 303(d) list for conventional or other pollutants as described in section 3.2 and Table 3.2 of the Water Quality Control Policy for Developing California’s Clean Water Act Section 303(d) List. However, the narrative objective that the evaluation guideline evaluates states that "the natural receiving water temperature of surface waters shall not be altered by discharges of wastewater unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses." State Water Resources Control Board has not determined whether the measured exceedances are due to discharges of wastewater and is therefore unable to determine if the water quality objective is met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158736, Temperature, water	Region 7
Havasu, Lake

LOE ID:

352487

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 8 of 16 samples exceeded the water quality threshold for Temperature.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The natural receiving water temperature of surface waters shall not be altered by discharges of wastewater unless
it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not
adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158736, Temperature, water	Region 7
Havasu, Lake

LOE ID:

352489

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 4 of 8 samples exceeded the water quality threshold for Temperature.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158736, Temperature, water	Region 7
Havasu, Lake

LOE ID:

352488

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	155121	Region 7
Havasu, Lake

Pollutant:	Terbufos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155121, Terbufos	Region 7
Havasu, Lake

LOE ID:

319779

Pollutant:

Terbufos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Benzo(g,h,i)Perylene, Benzo(e)Pyrene, Biphenyl, or Terbufos for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155202	Region 7
Havasu, Lake

Pollutant:	Terbuthylazine
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155202, Terbuthylazine	Region 7
Havasu, Lake

LOE ID:

319122

Pollutant:

Terbuthylazine

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Propazine, or Terbuthylazine for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155198	Region 7
Havasu, Lake

Pollutant:	Terbutryn
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155198, Terbutryn	Region 7
Havasu, Lake

LOE ID:

319796

Pollutant:

Terbutryn

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ametryn, Prometryn, Simetryn, or Terbutryn for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155122	Region 7
Havasu, Lake

Pollutant:	Tetrachloroethylene/PCE
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155122, Tetrachloroethylene/PCE	Region 7
Havasu, Lake

LOE ID:

321260

Pollutant:

Tetrachloroethylene/PCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155122, Tetrachloroethylene/PCE	Region 7
Havasu, Lake

LOE ID:

320095

Pollutant:

Tetrachloroethylene/PCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155123	Region 7
Havasu, Lake

Pollutant:	Tetrachlorvinphos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155123, Tetrachlorvinphos	Region 7
Havasu, Lake

LOE ID:

320328

Pollutant:

Tetrachlorvinphos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Chlorfenvinphos, Cuomaphos, Dicrotophos, Fenchchlorphos, Dyfonate, Leptophos, Merphos, Mevinphos, Tetrachlorvinphos, or Chlorpyrifos Methyl for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	164454	Region 7
Havasu, Lake

Pollutant:	Thallium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 164454, Thallium	Region 7
Havasu, Lake

LOE ID:

5150

Pollutant:

Thallium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Ten water quality samples were taken at 5 locations on the lake, generally collected from 3/18/1997 through 1/28/2004. Of these total samples, none exceeded the CTR criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria of 1.7 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 56227, 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Ten discrete samples were collected. Samples were generally collected from 3/18/1997 through 1/28/2004. Samples were collected on 2 discrete dates in 1997, 2 dates in 2001, 1 date in 2003, and 2 dates in 2004.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	172158	Region 7
Havasu, Lake

Pollutant:	Thiobencarb
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 172158, Thiobencarb	Region 7
Havasu, Lake

LOE ID:

320245

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 172158, Thiobencarb	Region 7
Havasu, Lake

LOE ID:

321261

Pollutant:

Thiobencarb/Bolero

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155193	Region 7
Havasu, Lake

Pollutant:	Thionazin
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155193, Thionazin	Region 7
Havasu, Lake

LOE ID:

320358

Pollutant:

Thionazin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155186	Region 7
Havasu, Lake

Pollutant:	Tokuthion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155186, Tokuthion	Region 7
Havasu, Lake

LOE ID:

320544

Pollutant:

Tokuthion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Ethion, Carbophenothion, Dichlofenthion, Dioxathion, Parathion, Fenitrothion, Fensulfothion, Fenthion, Malathion, Methidathion, Methyl Parathion, or Tokuthion for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155126	Region 7
Havasu, Lake

Pollutant:	Toluene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed. Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s) Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155126, Toluene	Region 7
Havasu, Lake

LOE ID:

321269

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155126, Toluene	Region 7
Havasu, Lake

LOE ID:

5161

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Two water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 10 acceptable water quality samples were generally collected from 3/2/2000 through 7/02/2001. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) of 0.15 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/02/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155126, Toluene	Region 7
Havasu, Lake

LOE ID:

5147

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criteria of 6800 ug/l for the protection of human health when consuming water and organisms from aquatic systems (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/02/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155126, Toluene	Region 7
Havasu, Lake

LOE ID:

321049

Pollutant:

Toluene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158737	Region 7
Havasu, Lake

Pollutant:	Total Dissolved Solids
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Five of the 132 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of the 132 samples exceed the threshold and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158737, Total Dissolved Solids	Region 7
Havasu, Lake

LOE ID:

334266

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Total Dissolved Solids.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

California Secondary Maximum Contaminant Levels (MCLs) for consumer acceptance objective for total dissolved solids is 1000 mg/L.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158737, Total Dissolved Solids	Region 7
Havasu, Lake

LOE ID:

334268

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for Total Dissolved Solids.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

California Secondary Maximum Contaminant Levels (MCLs) for consumer acceptance objective for total dissolved solids is 1000 mg/L.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158737, Total Dissolved Solids	Region 7
Havasu, Lake

LOE ID:

126826

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 5 of 5 samples exceeded the water quality standard for Total Dissolved Solids.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

California Secondary Maximum Contaminant Levels (MCLs) for consumer acceptance objective for total dissolved solids is 500 mg/L.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158737, Total Dissolved Solids	Region 7
Havasu, Lake

LOE ID:

5166

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

102

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

One hundred two water quality measurements were taken at 6 locations on the lake, generally collected from 7/26/1994 through 3/15/2006. Of these total measurements, none exceeded the CDPH SMCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 1,000 mg/l for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Measurements were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099, 100144).

Temporal Representation:

One hundred two discrete measurements were collected. Measurements were generally collected from 7/26/1994 through 3/15/2006. Measurements were collected on 3 discrete dates in 1994, , 16 dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998, 2 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, 2 dates in 2004, and 2 dates in 2006.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

QAPP Information Reference(s):


DECISION ID	155127	Region 7
Havasu, Lake

Pollutant:	Toxaphene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s).

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155127, Toxaphene	Region 7
Havasu, Lake

LOE ID:

126266

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Toxaphene. Although data was collected for 1 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for toxaphene in fish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets. (Klasing, S., and R. Brodberg, 2008)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155127, Toxaphene	Region 7
Havasu, Lake

LOE ID:

126652

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Toxaphene. Although data was collected for 1 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum toxaphene concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155127, Toxaphene	Region 7
Havasu, Lake

LOE ID:

319716

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Acenaphthene, Aldrin, Chlorpyrifos, Diazinon, or Toxaphene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155127, Toxaphene	Region 7
Havasu, Lake

LOE ID:

126268

Pollutant:

Toxaphene

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Waterboard staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality standard for Toxaphene. Although data was collected for 1 fish species (1 composite(s) of Channel Catfish each composed of 20 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP RWB7 Monitoring.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data was collected from 1 station(s) with the station code(s): 714PLH216.

Temporal Representation:

Data for this line of evidence were collected between 2014-11-10 and 2014-11-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	155129	Region 7
Havasu, Lake

Pollutant:	Trichlorfon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155129, Trichlorfon	Region 7
Havasu, Lake

LOE ID:

320359

Pollutant:

Trichlorfon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155130	Region 7
Havasu, Lake

Pollutant:	Trichloroethylene/TCE
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155130, Trichloroethylene/TCE	Region 7
Havasu, Lake

LOE ID:

321270

Pollutant:

Trichloroethylene/TCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155130, Trichloroethylene/TCE	Region 7
Havasu, Lake

LOE ID:

320096

Pollutant:

Trichloroethylene/TCE

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155131	Region 7
Havasu, Lake

Pollutant:	Trichlorofluoromethane (CFC-11)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155131, Trichlorofluoromethane (CFC-11)	Region 7
Havasu, Lake

LOE ID:

319083

Pollutant:

Trichlorofluoromethane (CFC-11)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 5/2002 at 1 location in the interior of the lake. This sample did not exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Levels (MCLs) for the protection of human health were used for the following constituents: 0.1 mg/l Styrene, and 0.15 mg/l Trichlorofluoromethane (CFC-11) (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Sample was collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. A water sample was collected in 5/2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155194	Region 7
Havasu, Lake

Pollutant:	Trichloronate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155194, Trichloronate	Region 7
Havasu, Lake

LOE ID:

320360

Pollutant:

Trichloronate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Oxychlordane, Perylene, Phorate, Phosmet, Phosphamidon, Sulfotep, Tedion, Thionazin, Trichloronate, or Trichlorfon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158738	Region 7
Havasu, Lake

Pollutant:	Turbidity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Five of the 43 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of the 43 samples exceed the threshold and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158738, Turbidity	Region 7
Havasu, Lake

LOE ID:

336395

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Turbidity.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

California Maximum Contaminant Levels (MCLs) apply to ambient surface waters under the Basin Plan's 'Chemical Constituents' objective. The Secondary MCL for turbidity is 5 NTU. Calculation of a numeric objective for other beneficial uses requires comparison with upstream or other background data which may not be available as part of the data used for water quality assessment.

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158738, Turbidity	Region 7
Havasu, Lake

LOE ID:

334272

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Turbidity.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2018-04-18 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158738, Turbidity	Region 7
Havasu, Lake

LOE ID:

334269

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Turbidity.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-08-10 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158738, Turbidity	Region 7
Havasu, Lake

LOE ID:

5136

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Thirty three measurements were taken at 3 locations on the lake, generally collected from 7/27/1994 through 1/28/2004. Of these total measurements , 3 exceeded the CDPH SMCL. The exceedences were found in measurements collected on 3/03/1995 at one location, and 5/16/1996 at two locations (100099, and 100100) (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 5 NTU for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Measurements were collected from the following Lake Havasu locations: near the north end (100100, 100101),and midlake (100099).

Temporal Representation:

Thirty three discrete measurements were collected. Measurements were generally collected from 7/27/1994 through 9/30/2003. Measurements were collected on 1 discrete date in 1994, 8 dates in 1995, 6 dates in 1996, 2 dates in 1997, 2 dates in 1998 , 2 dates in 2000, 6 dates in 2001, 2 dates in 2002, 3 dates in 2003, and 1 date in 2004. The exceedences were found in measurements collected from 3/03/1995 through 5/16/1996.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 158738, Turbidity	Region 7
Havasu, Lake

LOE ID:

7605

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water quality measurements were collected in 2002 at 1 location in the interior of the lake. Of these total measurements , none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 5 NTU for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Measurements were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water quality measurements were collected. Water quality measurements were collected twice in 2002. Measurements were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158739	Region 7
Havasu, Lake

Pollutant:	Vanadium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158739, Vanadium	Region 7
Havasu, Lake

LOE ID:

334275

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Vanadium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The 0.1 mg/L criteria is for the recommended maximum concentrations of vanadium in irrigation water

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2017-11-15

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158739, Vanadium	Region 7
Havasu, Lake

LOE ID:

334278

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Vanadium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water. These criteria were used to translate narrative water quality objectives for chemical constituents that prohibit chemicals in concentrations that would impair agricultural uses of water. The 0.1 mg/L criteria is for the recommended maximum concentrations of vanadium in irrigation water

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158739, Vanadium	Region 7
Havasu, Lake

LOE ID:

334276

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Vanadium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Drinking water notification levels are published by the Division of Drinking Water and are for chemicals for which there is no drinking water MCL. If a notification level is exceeded, local government notification is required and customer notification is recommended. The criteria for Vanadium is 0.05 mg/L.

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-14 and 2017-11-14

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158739, Vanadium	Region 7
Havasu, Lake

LOE ID:

334273

Pollutant:

Vanadium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Vanadium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Drinking Water Notification and Response Levels: An Overview

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-11-15 and 2017-11-15

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	155133	Region 7
Havasu, Lake

Pollutant:	Xylenes (total) (mixed)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155133, Xylenes (total) (mixed)	Region 7
Havasu, Lake

LOE ID:

321271

Pollutant:

Xylenes (total) (mixed)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155133, Xylenes (total) (mixed)	Region 7
Havasu, Lake

LOE ID:

5164

Pollutant:

Xylenes (total) (mixed)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Twelve water samples were taken at 4 locations on the lake. Three water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 9 acceptable water quality samples were generally collected from 3/02/2000 through 7/5/2001. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 1.75 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099).

Temporal Representation:

Twelve discrete samples were collected. Samples were generally collected from 3/02/2000 through 7/05/2001. Samples were collected on 3 discrete dates in 2000, and 5 dates in 2001.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155134	Region 7
Havasu, Lake

Pollutant:	Zinc
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

126739

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Zinc.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334286

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved zinc criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 120 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-01-31

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

7624

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Consensus Based Sediment Quality Guideline Probable Effects Concentration (PEC) of 459 mg/kg for the protection of freshwater organisms to toxic effects (Macdonald et al, 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

126693

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Zinc.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

319802

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR hardness dependent criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

319063

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

320246

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

319098

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334282

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334285

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2017-01-31 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334293

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-01-31

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334292

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2017-01-31 and 2017-01-31

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334287

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334284

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

334291

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155134, Zinc	Region 7
Havasu, Lake

LOE ID:

126790

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Zinc.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	155187	Region 7
Havasu, Lake

Pollutant:	alpha-Chlordene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155187, alpha-Chlordene	Region 7
Havasu, Lake

LOE ID:

319134

Pollutant:

alpha-Chlordene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of alpha-Chlordene, or gamma-Chlordene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155187, alpha-Chlordene	Region 7
Havasu, Lake

LOE ID:

319117

Pollutant:

alpha-Chlordene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of alpha-Chlordene, or gamma-Chlordene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155058	Region 7
Havasu, Lake

Pollutant:	alpha-Endosulfan (Endosulfan 1)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available Multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with modern database requirements. Detailed information is included in the replacement LOE(s). LOEs for this waterbody-pollutant combination from previous cycles were reviewed, determined to be inaccurate, and removed.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155058, alpha-Endosulfan (Endosulfan 1)	Region 7
Havasu, Lake

LOE ID:

46150

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan I. One composite (20 fish per composite) was generated from one species: common carp. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total Endosulfan concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155058, alpha-Endosulfan (Endosulfan 1)	Region 7
Havasu, Lake

LOE ID:

321050

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155058, alpha-Endosulfan (Endosulfan 1)	Region 7
Havasu, Lake

LOE ID:

319372

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Endosulfan 1, Endosulfan 2, or Endosulfan Sulfate for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155058, alpha-Endosulfan (Endosulfan 1)	Region 7
Havasu, Lake

LOE ID:

46149

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155058, alpha-Endosulfan (Endosulfan 1)	Region 7
Havasu, Lake

LOE ID:

46156

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/5/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155058, alpha-Endosulfan (Endosulfan 1)	Region 7
Havasu, Lake

LOE ID:

320076

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155026	Region 7
Havasu, Lake

Pollutant:	alpha.-BHC (Benzenehexachloride or alpha-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155026, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Havasu, Lake

LOE ID:

321051

Pollutant:

alpha.-BHC (Benzenehexachloride or alpha-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155026, alpha.-BHC (Benzenehexachloride or alpha-HCH)	Region 7
Havasu, Lake

LOE ID:

319641

Pollutant:

alpha.-BHC (Benzenehexachloride or alpha-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155085	Region 7
Havasu, Lake

Pollutant:	beta-BHC (Benzenehexachloride or beta-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155085, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Havasu, Lake

LOE ID:

321052

Pollutant:

beta-BHC (Benzenehexachloride or beta-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155085, beta-BHC (Benzenehexachloride or beta-HCH)	Region 7
Havasu, Lake

LOE ID:

319642

Pollutant:

beta-BHC (Benzenehexachloride or beta-HCH)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of alpha-HCH, beta-HCH, Hexachlorobenzene, or Methoxychlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155107	Region 7
Havasu, Lake

Pollutant:	beta-Endosulfan (Endosulfan 2)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155107, beta-Endosulfan (Endosulfan 2)	Region 7
Havasu, Lake

LOE ID:

321062

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155107, beta-Endosulfan (Endosulfan 2)	Region 7
Havasu, Lake

LOE ID:

319373

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of Endosulfan 1, Endosulfan 2, or Endosulfan Sulfate for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155107, beta-Endosulfan (Endosulfan 2)	Region 7
Havasu, Lake

LOE ID:

320077

Pollutant:

beta-Endosulfan (Endosulfan 2)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155052	Region 7
Havasu, Lake

Pollutant:	cis-1,2-Dichloroethylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155052, cis-1,2-Dichloroethylene	Region 7
Havasu, Lake

LOE ID:

321279

Pollutant:

cis-1,2-Dichloroethylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155210	Region 7
Havasu, Lake

Pollutant:	cis-1,3-Dichloropropene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155210, cis-1,3-Dichloropropene	Region 7
Havasu, Lake

LOE ID:

319879

Pollutant:

cis-1,3-Dichloropropene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155159	Region 7
Havasu, Lake

Pollutant:	cis-Nonachlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155159, cis-Nonachlor	Region 7
Havasu, Lake

LOE ID:

319137

Pollutant:

cis-Nonachlor

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of cis-Nonachlor, or trans-Nonachlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155159, cis-Nonachlor	Region 7
Havasu, Lake

LOE ID:

319144

Pollutant:

cis-Nonachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of cis-Nonachlor, or trans-Nonachlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155125	Region 7
Havasu, Lake

Pollutant:	delta-BHC (Benzenehexachloride or delta-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155125, delta-BHC (Benzenehexachloride or delta-HCH)	Region 7
Havasu, Lake

LOE ID:

320084

Pollutant:

delta-BHC (Benzenehexachloride or delta-HCH)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155188	Region 7
Havasu, Lake

Pollutant:	gama-Chlordene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155188, gama-Chlordene	Region 7
Havasu, Lake

LOE ID:

319118

Pollutant:

gama-Chlordene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of alpha-Chlordene, or gamma-Chlordene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155188, gama-Chlordene	Region 7
Havasu, Lake

LOE ID:

319216

Pollutant:

gama-Chlordene

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of alpha-Chlordene, or gamma-Chlordene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155091	Region 7
Havasu, Lake

Pollutant:	m-Dichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155091, m-Dichlorobenzene	Region 7
Havasu, Lake

LOE ID:

321063

Pollutant:

m-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155208	Region 7
Havasu, Lake

Pollutant:	n-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155208, n-Butylbenzene	Region 7
Havasu, Lake

LOE ID:

320085

Pollutant:

n-Butylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155148	Region 7
Havasu, Lake

Pollutant:	n-Propylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155148, n-Propylbenzene	Region 7
Havasu, Lake

LOE ID:

320097

Pollutant:

n-Propylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155104	Region 7
Havasu, Lake

Pollutant:	o-Dichlorobenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155104, o-Dichlorobenzene	Region 7
Havasu, Lake

LOE ID:

321280

Pollutant:

o-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155104, o-Dichlorobenzene	Region 7
Havasu, Lake

LOE ID:

321064

Pollutant:

o-Dichlorobenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155106	Region 7
Havasu, Lake

Pollutant:	o-Xylene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155106, o-Xylene	Region 7
Havasu, Lake

LOE ID:

319124

Pollutant:

o-Xylene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Dibenzothiophene, or o-Xylene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155109	Region 7
Havasu, Lake

Pollutant:	p-Cymene (p-Isopropyltoluene)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155109, p-Cymene (p-Isopropyltoluene)	Region 7
Havasu, Lake

LOE ID:

319503

Pollutant:

p-Cymene (p-Isopropyltoluene)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of 2-Chlorotoluene, 4-Chlorotoluene, or p-Cymene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155110	Region 7
Havasu, Lake

Pollutant:	p-Dichlorobenzene (DCB)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155110, p-Dichlorobenzene (DCB)	Region 7
Havasu, Lake

LOE ID:

321065

Pollutant:

p-Dichlorobenzene (DCB)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155110, p-Dichlorobenzene (DCB)	Region 7
Havasu, Lake

LOE ID:

321281

Pollutant:

p-Dichlorobenzene (DCB)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158733	Region 7
Havasu, Lake

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for conventional or other pollutants (Table 3.2 of the Listing Policy). The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334158

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan for the Colorado River Basin Region's water quality objective for all surface waters states the following: Since the regional waters are somewhat alkaline, pH shall range from 6.0-9.0. Discharges shall not cause any changes in pH detrimental to beneficial water uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

335878

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334131

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Aquaculture

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334159

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Aquaculture

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

336030

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Aquaculture

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334138

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334178

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

335846

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334098

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334147

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

335843

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334139

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334115

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

7706

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two measurements were collected in 2002 at 1 location in the interior of the lake. Of these total measurements, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: Since the regional waters are somewhat alkaline, pH shall range from 6.0-9.0 (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Measurements were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water quality measurements were collected. Water quality measurements were collected twice in 2002. Measurements were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334130

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

335881

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334109

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334149

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

335804

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334097

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126749

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126860

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Aquaculture

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126845

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126778

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126795

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126712

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

5173

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

112

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

One hundred twelve water quality measurements were taken at 7 locations on the lake, generally collected from 8/19/1992 through 3/15/2006. Of these total measurements, none exceeded the Basin Plan Objective (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Since the regional waters are somewhat alkaline, pH shall range from 6.0-9.0 (CRBRWQCB, 2006).).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Measurements were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099, 100144).

Temporal Representation:

One hundred twelve discrete measurements were collected. Measurements were generally collected from 8/19/1992 through 3/15/2006. Measurements were collected on 2 discrete dates in 1992, 2 dates in 1993, 5 dates in 1994, 16 dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998 , 3 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, 2 dates in 2004, and 2 dates in 2006.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

126794

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality standard for pH.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

334148

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 16 samples exceeded the water quality threshold for pH.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158733, pH	Region 7
Havasu, Lake

LOE ID:

336075

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB7 Monitoring data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	155149	Region 7
Havasu, Lake

Pollutant:	sec-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155149, sec-Butylbenzene	Region 7
Havasu, Lake

LOE ID:

320098

Pollutant:

sec-Butylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155150	Region 7
Havasu, Lake

Pollutant:	tert-Butylbenzene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155150, tert-Butylbenzene	Region 7
Havasu, Lake

LOE ID:

320099

Pollutant:

tert-Butylbenzene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of delta-BHC, Bromobenzene, 1,2,4-Trimethybenzene, 135-Trimethylbenzene, Cumene, n-Propylbenzene, n-Butylbenzene, sec-Butylbenzene, or tert-Butylbenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155211	Region 7
Havasu, Lake

Pollutant:	trans-1,3-Dichloropropene
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155211, trans-1,3-Dichloropropene	Region 7
Havasu, Lake

LOE ID:

319880

Pollutant:

trans-1,3-Dichloropropene

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of Methyl Chloride, Chloroethane, Dichlorodifluoromethane, cis-1,3-Dichloropropene, trans-1,3-Dichloropropene, or 1,2,3-Trichlorobenzene for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	155160	Region 7
Havasu, Lake

Pollutant:	trans-Nonachlor
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 155160, trans-Nonachlor	Region 7
Havasu, Lake

LOE ID:

319138

Pollutant:

trans-Nonachlor

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).No evaluation guidelines for the sediment fractions of cis-Nonachlor, or trans-Nonachlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155160, trans-Nonachlor	Region 7
Havasu, Lake

LOE ID:

319145

Pollutant:

trans-Nonachlor

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).No evaluation guidelines for the dissolved fractions of cis-Nonachlor, or trans-Nonachlor for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	158730	Region 7
Havasu, Lake

Pollutant:	Iron
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Six of the 57 samples exceed the threshold for the municipal beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of the 57 samples exceed the threshold for the municipal beneficial use and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

334002

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations are intended protect freshwater aquatic organisms from chronic exposures and are expressed as 4-day average concentrations. The evaluation guideline for iron is 1,000 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-02-27

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

333994

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for iron is 0.3 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-02-27

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

126716

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Iron.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

The California Secondary MCL for iron is 0.3 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

333993

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2019-02-27

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

333995

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 2 of 4 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for iron is 0.3 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-01-31

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

333992

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 4 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-01-31

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

333999

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 4 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-01-31

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 158730, Iron	Region 7
Havasu, Lake

LOE ID:

5132

Pollutant:

Iron

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Sixty-three water samples were taken at 5 locations on the lake. Sixteen water sample results could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 47 acceptable water quality samples were generally collected from 3/2/1995 through 1/8/2004. Of these total samples , 3 exceeded the CDPH SMCL. The exceedences were found in samples collected on 7/27/1995, 12/11/1996, and 3/18/1997, from three different locations (56227, 100098, and 100102) (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 0.3 mg/l for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Sixty-three discrete water samples were collected. Water samples were generally collected and analyzed from 3/2/1995 through 1/8/2004.Samples were collected on 11 discrete dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998 , 2 dates in 2000, 8 dates in 2001, 2 dates in 2002, and 1 date in 2003. The exceedences were found in samples collected from 7/27/1995 through 3/18/1997.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods, similar to ADEQ, 2005. Sample analysis was carried out using USEPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	155087	Region 7
Havasu, Lake

Pollutant:	Lead
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant in water for the cold beneficial use in the dissolved fraction. Two of the 9 samples exceed the threshold. Four lines of evidence are available in the administrative record to assess this pollutant in water for the warm beneficial use in the dissolved fraction. Two of the 11 samples exceed the threshold. The following multi-pollutant LOEs were removed and replaced by single-pollutant LOEs to comply with updated database requirements: 7699, 7692, 7636. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Three lines of evidence are available in the administrative record to assess this pollutant in water for the cold beneficial use in the dissolved fraction. Two of the 9 samples exceed the threshold. Four lines of evidence are available in the administrative record to assess this pollutant in water for the warm beneficial use in the dissolved fraction. Two of the 11 samples exceed the threshold. This exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

126714

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Lead.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

126852

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Lead.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

126769

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality standard for Lead.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

126857

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for Lead.

Data Reference:

Water quality data for federal, state, and tribal agencies submitted through the US EPA STorage and RETrival (STORET) database for the 2018 listing cycle.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before January 8, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 3 monitoring site(s) (21ARIZ_WQX-CLHAV-199.6, 21ARIZ_WQX-CLHAV-207.7, 21ARIZ_WQX-CLHAV-217)

Temporal Representation:

The samples were collected between the dates of 2015-10-19 and 2015-10-20

Environmental Conditions:

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

5174

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified below¿Lead 0.05 mg/l (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

5141

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Hardness Dependent Criterion Maximum Concentration (CMCs) for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334005

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

321147

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the PEC (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

319651

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334015

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved lead criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334013

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334010

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334018

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2016-08-10

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

319786

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples, none exceeded the CTR hardness dependent criteria (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334012

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2017-11-15

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 155087, Lead	Region 7
Havasu, Lake

LOE ID:

334009

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for lead in the Basin Plan is 0.015 mg/L (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-10-20 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	163851	Region 7
Havasu, Lake

Pollutant:	Microcystins
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Nine lines of evidence are available in the administrative record to assess this pollutant. Eleven of the 18 samples exceed the GUIDELINE for MUN (0.3 ug/L, EPA). Five of the 18 samples exceed the GUIDELINE for REC-1 (6 ug/L, CCHAB). Five of the 18 samples exceed the GUIDELINE for WILD (2 ug/L, OEHHA). Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Eleven of the 18 samples exceed the GUIDELINE for MUN (0.3 ug/L, EPA). Five of the 18 samples exceed the GUIDELINE for REC-1 (6 ug/L, CCHAB). Five of the 18 samples exceed the GUIDELINE for WILD (2 ug/L, OEHHA) and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334043

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 7 of 10 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

USEPA 10-day microcystin health advisory for bottle-fed infants and young children of pre-school age is 0.3 ug/L.

Guideline Reference:

Drinking Water Health Advisory for the Cyanobacterial Microcystin Toxins

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-04-29 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334033

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Arizona Department Of Environmental Quality data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

USEPA 10-day microcystin health advisory for bottle-fed infants and young children of pre-school age is 0.3 ug/L.

Guideline Reference:

Drinking Water Health Advisory for the Cyanobacterial Microcystin Toxins

Spatial Representation:

The samples were collected at 1 monitoring site: 21ARIZ_WQX-CLHAV-207.7 (LAKE HAVASU - BOR SITE OFF PARTNER'S POINT).

Temporal Representation:

The samples were collected between the dates of 2015-04-29 and 2015-04-29

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334034

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Cyanobacteria and Harmful Algal Bloom (CCHAB) Network established 6 ug/L of microcystins as the water concentration protective of swimmers and other contact recreational users including water-skiing/jet-skiing, fishing, boating, sail boarding, and canoeing.

Guideline Reference:

Appendix to the CCHAB preliminary changes to the statewide voluntary guidance on cyanoHABs in recreational waters, January 2016. Appendix A. Description of cyanotoxin triggers in recreational waters.

Spatial Representation:

The samples were collected at 1 monitoring site: 21ARIZ_WQX-CLHAV-207.7 (LAKE HAVASU - BOR SITE OFF PARTNER'S POINT).

Temporal Representation:

The samples were collected between the dates of 2015-04-29 and 2015-04-29

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334035

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

California Office of Environmental Health Hazard Assessment (OEHHA) established 2 ug/L of microcystins as the subchronic water concentration for dog intake/ingestion (Office of Environmental Health Hazard Assessment Public Health Action Level for microcystin and Human Recreational Uses (May 2012)). OEHHA Action Level for subchronic water intake, dog.

Guideline Reference:

Toxicological Summary and Suggested Action Levels to Reduce Potential Adverse Health Effects of Six Cyanotoxins

Spatial Representation:

The samples were collected at 1 monitoring site: 21ARIZ_WQX-CLHAV-207.7 (LAKE HAVASU - BOR SITE OFF PARTNER'S POINT).

Temporal Representation:

The samples were collected between the dates of 2015-04-29 and 2015-04-29

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334036

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 3 of 10 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Appendix to the CCHAB preliminary changes to the statewide voluntary guidance on cyanoHABs in recreational waters, January 2016. Appendix A. Description of cyanotoxin triggers in recreational waters.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-04-29 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334042

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 7 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Toxicological Summary and Suggested Action Levels to Reduce Potential Adverse Health Effects of Six Cyanotoxins

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-04-26 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334041

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 1 of 7 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Appendix to the CCHAB preliminary changes to the statewide voluntary guidance on cyanoHABs in recreational waters, January 2016. Appendix A. Description of cyanotoxin triggers in recreational waters.

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-04-26 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334037

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 3 of 10 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

Guideline Reference:

Toxicological Summary and Suggested Action Levels to Reduce Potential Adverse Health Effects of Six Cyanotoxins

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-04-29 and 2018-11-07

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 163851, Microcystins	Region 7
Havasu, Lake

LOE ID:

334040

Pollutant:

Microcystins

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 3 of 7 samples exceeded the water quality threshold for Microcystins, Total.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

USEPA 10-day microcystin health advisory for bottle-fed infants and young children of pre-school age is 0.3 ug/L.

Guideline Reference:

Drinking Water Health Advisory for the Cyanobacterial Microcystin Toxins

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2016-04-26 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	169576	Region 7
Havasu, Lake

Pollutant:	Specific Conductivity
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
TMDL Priority:	Low
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. Twenty-three of the 138 samples exceed the threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Twenty-three of the 138 samples exceed the threshold and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 169576, Specific Conductivity	Region 7
Havasu, Lake

LOE ID:

7681

Pollutant:

Specific Conductance

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two measurements were collected in 2002 at 1 location in the interior of the lake. Of these total measurements, none exceeded the CDPH SMCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 1600 umhos for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Measurements were collected near the California Nevada Border. Measurements were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water quality measurements were collected. Water quality measurements were collected twice in 2002. Measurements were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 169576, Specific Conductivity	Region 7
Havasu, Lake

LOE ID:

5134

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

110

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

One hundred and ten measurements were taken at 6 locations on the lake, generally collected from 8/19/1992 through 3/15/2006. Of these total measurements, 1 exceeded the CDPH SMCL. The exceedence was found in a measurement collected on 7/07/1997 from one location on the south end (56227) (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 1600 umhos/cm for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Measurements were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

One hundred and ten discrete measurements were collected. Measurements were generally collected from 8/19/1992 through 3/15/2006. Measurements were collected on 2 discrete dates in 1992, 2 in 1993, 5 dates in 1994, 15 dates in 1995, 8 dates in 1996, 4 dates in 1997, 2 dates in 1998 , 4 dates in 2000, 8 dates in 2001, 2 dates in 2002, 3 dates in 2003, 2 dates in 2004, and 2 dates in 2006. The exceedence was found in a measurement collected on 7/07/1997.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 169576, Specific Conductivity	Region 7
Havasu, Lake

LOE ID:

336296

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Tissue, Toxicity, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 7

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: 714PLH216 (Lake Havasu_BOG).

Temporal Representation:

The samples were collected between the dates of 2020-10-26 and 2020-10-26

Environmental Conditions:

QAPP Information:

General SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 169576, Specific Conductivity	Region 7
Havasu, Lake

LOE ID:

334237

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 15 of 16 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2581 (110671).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2019-06-05

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691

Line of Evidence (LOE) for Decision ID 169576, Specific Conductivity	Region 7
Havasu, Lake

LOE ID:

334236

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed AZDEQ_SW data for Havasu, Lake to determine beneficial use support and results are as follows: 7 of 9 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 7

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Colorado River Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Colorado River Basin Region (Includes amendments effective on or before March 30, 2019)

Evaluation Guideline:

The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).

Guideline Reference:

Title 22. Division 4. Chapter 15. Sections 64400 et seq. California Code of Regulations

Spatial Representation:

The samples were collected at 1 monitoring site: AZDEQ_SW-2598 (110795).

Temporal Representation:

The samples were collected between the dates of 2015-09-01 and 2017-06-13

Environmental Conditions:

QAPP Information:

AZDEQ SW QAPP 01/2021

QAPP Information Reference(s):

CRB-RWQCB o/b/o AZDEQ - AZDEQ SW QAPP 01/2021 - AZDEQ_SW - 402691


DECISION ID	78018	Region 7
Havasu, Lake

Pollutant:	Carbon (organic)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess organic Carbon consistent with Listing Policy section 3.6. No evaluation guidelines for the sediment fraction of organic Carbon for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the sediment fraction of organic Carbon for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 78018, Carbon (organic)	Region 7
Havasu, Lake

LOE ID:

29543

Pollutant:

Carbon (organic)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Three sediment samples were collected and analyzed in 2002 from 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guideline for the sediment fraction of Organic Carbon for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Three sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	71185	Region 7
Havasu, Lake

Pollutant:	Chromium (total)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. However, a use rating of LOE No. 7699 is changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 37 water samples exceeded either the California Toxics Rule criteria or the drinking water MCL. None of two sediment samples exceeded the sediment quality guideline. These do not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 71185, Chromium (total)	Region 7
Havasu, Lake

LOE ID:

5142

Pollutant:

Chromium (total)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) Criterion Maximum Concentration (CMC) of 1724 ug/l for the protection of freshwater aquatic life uses (USEPA, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100100, 100101),and midlake (100102, 100099).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	70977	Region 7
Havasu, Lake

Pollutant:	Enterococcus
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. However, a use rating of LOE Nos. 7611 and 7608 are changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 2 water samples exceeded the Basin Plan Enterococcus water quality objectives for RECI or RECII beneficial uses. These do not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 70977, Enterococcus	Region 7
Havasu, Lake

LOE ID:

7611

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable Enterococcus density is 305 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70977, Enterococcus	Region 7
Havasu, Lake

LOE ID:

7608

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable Enterococcus density is 61 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70985	Region 7
Havasu, Lake

Pollutant:	Escherichia coli (E. coli)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. However, a use rating of LOE Nos. 5178,5177,7703, and 7697 are changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 7 water samples exceeded the Basin Plan E. coli water quality objectives for RECI or RECII beneficial uses. These do not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 70985, Escherichia coli (E. coli)	Region 7
Havasu, Lake

LOE ID:

7697

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable E. coli density is 235 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70985, Escherichia coli (E. coli)	Region 7
Havasu, Lake

LOE ID:

7703

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the Basin Plan Objective (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan:In the Colorado River the maximum allowable E. coli density is 1175 MPN/ 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 70985, Escherichia coli (E. coli)	Region 7
Havasu, Lake

LOE ID:

5178

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Six water samples were taken at 5 locations on the lake. One water sample result could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 5 acceptable water quality samples were generally collected from 9/01/1999 through 4/24/2003. Of these total samples, none exceeded the Basin Plan Objective (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan:¿for the Colorado River, the following maximum allowables shall apply:REC2 E. Coli 1175 per 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099, 100144).

Temporal Representation:

Six discrete samples were collected. Samples were generally collected from 9/01/1999 through 4/24/2003. Samples were collected on 2 discrete dates in 1999, 3 dates in 2001, 2 dates in 2002, and 1 date in 2003.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

Line of Evidence (LOE) for Decision ID 70985, Escherichia coli (E. coli)	Region 7
Havasu, Lake

LOE ID:

5177

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Six water samples taken at 5 locations on the lake. One water sample result could not be used in this assessment because either the sample results were non-detect and the detection limit was above the criteria concentration or the samples results were non-detect and the detection limit could not be determined. The 5 acceptable water quality samples were generally collected from 9/01/1999 through 4/24/2003. Of these total samples , none exceeded the Basin Plan Objective (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan:¿for the Colorado River, the following maximum allowables shall apply:REC1 E. Coli 235 per 100 ml (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098), near the north end (100101),and midlake (100102, 100099, 100144).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.


DECISION ID	71361	Region 7
Havasu, Lake

Pollutant:	Hexachlorocyclohexane (HCH) (mixture)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.5 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. This line of evidence received a Use Rating of Insufficient Information because there was only one sample reported in the line of evidence. According to Table 3.1 of the Listing Policy, the minimum number of samples required is 2. This sample did not exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 1 fish tissue sample exceeded the National Academy of Sciences fish tissue guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 71361, Hexachlorocyclohexane (HCH) (mixture)	Region 7
Havasu, Lake

LOE ID:

6727

Pollutant:

Hexachlorocyclohexane (HCH) (mixture)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

One fish fillet sample was taken at 1 location in the lake. The sample was generally collected in 10/1987. This sample did not exceed the NAS tissue guideline (TSMP, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

National Academy of Science (NAS) tissue guideline of 100 ug/kg for the protection of aquatic life uses (NAS, 1973).

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Samples were collected from the interior of Lake Havasu.

Temporal Representation:

One bluegill fillet composite sample was collected on 10/20/87.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Toxic Substances Monitoring Program 1991 Data Report. 93-1WQ. State Water Resources Control Board (SWRCB), Division of Water Quality. Sacramento, CA.


DECISION ID	76571	Region 7
Havasu, Lake

Pollutant:	Hydroxide
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Hydroxide consistent with Listing Policy section 3.1. No evaluation guidelines for the dissolved fraction of Hydroxide for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guideline for the dissolved fraction of Hydroxide for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 76571, Hydroxide	Region 7
Havasu, Lake

LOE ID:

29484

Pollutant:

Hydroxide

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Hydroxide for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in May.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	69639	Region 7
Havasu, Lake

Pollutant:	Perchlorate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. However, use ratings of LOE Nos. 755, 7614 and 5165 are changed from fully supporting to insufficient due to insufficient sample size required by the Listing Policy to determine if the water quality objectives are met. No new data were assessed in current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. No measurements of perchlorate exceed the guideline. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. A remedial effort has been underway since October 2002 to remove perchlorate from a source near Las Vegas, NV. Monitoring data collected before October 2002 are no longer representative of water quality in the River. 4. After September 2002, none of 31 water samples exceed the evaluation guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 69639, Perchlorate	Region 7
Havasu, Lake

LOE ID:

756

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Monthly samples were collected by the Metropolitan Water District (MWD) of S. CA at the Colorado River Aqueduct at Lake Havasu (MWD of Southern California, 2001). Twelve-month averages of the perchlorate concentrations were calculated and compared to the benchmark value of 6 ppb. Of the annual averages from 1998 to 2003 (6 averages), 4 were greater than 6 ppb. The averages in 2002 and 2003 were less than 6 ppb. Of the 76 single samples 21 were greater than 6 ppb.

Note: Annual average concentration has declined from 6.4 ppb in 2000 to 4.8 ppb in 2003 (a 25% decrease) and further decreases are expected in 2004 and 2005 given the steady decline in the mass of perchlorate entering Lake Mead via Las Vegas Wash since early 2003.

Before October 2002, only 3 samples had concentrations of perchlorate below 6 ppb. After September 2002, there have been no exceedances in 26 measurements.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

OEHHA PHG = 6 ppb.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Samples were collected at the intake to the Colorado River Aqueduct at Lake Havasu near Parker Dam.

Temporal Representation:

Samples were collected monthly from 1998 through 2004. Presently available data are from January 1998 to November 2004.

Environmental Conditions:

QAPP Information:

MWD QA/QC.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 69639, Perchlorate	Region 7
Havasu, Lake

LOE ID:

5165

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Three water quality sample were taken at 3 locations on the lake, on 9/30/2003. Of these total samples, none exceeded the CDPH MCL criteria (USEPA, 2007).

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 0.006 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from the following Lake Havasu locations: near the north end (Station ID No. 100101),and midlake (100102, 100099).

Temporal Representation:

Three discrete samples were collected. The sample were all collected on 9/30/2003. Sample were collected on 1 discrete date in 2003.

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 69639, Perchlorate	Region 7
Havasu, Lake

LOE ID:

7614

Pollutant:

Perchlorate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake. Of these total samples , none exceeded the CDPH MCL (SWAMP, 2007).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Maximum Contaminant Level (MCL) of 0.006 mg/l for the protection of human health (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 69639, Perchlorate	Region 7
Havasu, Lake

LOE ID:

755

Pollutant:

Perchlorate

LOE Subgroup:

Narrative Description Data

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The source of perchlorate is a former perchlorate production site in Henderson, NV. At the site perchlorate enters a wash through groundwater and a surface seep. The perchlorate plume is intercepted at three locations and treated using ion exchange units and a biologically-based fluidized bed reactor. These treatment facilities are 99+ percent efficient at removing perchlorate.

The treatment facilities have been operational since October 2002. Substantial reductions in the perchlorate concentrations entering Lake Mead have been realized.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Henderson, NV.

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	76875	Region 7
Havasu, Lake

Pollutant:	Pheophytin a
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.7.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess Pheophytin a consistent with Listing Policy section 3.7.1. No evaluation guidelines for the dissolved fraction of Pheophytin a for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guideline for the dissolved fraction of Pheophytin a for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 76875, Pheophytin a	Region 7
Havasu, Lake

LOE ID:

29485

Pollutant:

Pheophytin a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

One water sample was collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Pheophytin a for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

One water sample was collected. The water sample was collected in 2002, in May.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	70541	Region 7
Havasu, Lake

Pollutant:	Salinity/TDS/Chlorides
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 102 water samples exceeded the drinking water secondary MCL and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 70541, Salinity/TDS/Chlorides	Region 7
Havasu, Lake

LOE ID:

5166

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

102

Number of Exceedances:

Data and Information Type:

Other Agencies/Organizations provided monitoring data

Data Used to Assess Water Quality:

Data Reference:

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

California Department of Public Health (CDPH) Drinking Water Secondary Maximum Contaminant Level (SMCL) of 1,000 mg/l for consumer acceptance (CCR, Title 22).

Guideline Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64449 Secondary Drinking Water Standards

Spatial Representation:

Measurements were collected from the following Lake Havasu locations: near the south end (Station ID No. 100098, 56227), near the north end (100101, 100100),and midlake (100102, 100099, 100144).

Temporal Representation:

Environmental Conditions:

QAPP Information:

Sampling was conducted in accordance with approved sampling methods similar to ADEQ, 2005. Sample analysis was carried out using EPA approved methods (USEPA, 2007).

QAPP Information Reference(s):

A Manual of Procedures for the Sampling of Surface Waters. Phoenix, AZ.

QAPP Information Reference(s):


DECISION ID	76575	Region 7
Havasu, Lake

Pollutant:	Streptococcus, fecal
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess fecal Streptococcus consistent with Listing Policy section 3.3. No evaluation guideline for the total density of fecal Streptococcus for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. Because there is no appropriate evaluation guideline, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guideline for the total density of fecal Streptococcus for the protection of human, animal or aquatic life in fresh waters could be found that meets the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 76575, Streptococcus, fecal	Region 7
Havasu, Lake

LOE ID:

29481

Pollutant:

Streptococcus, fecal

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guideline for Streptococcus for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	77194	Region 7
Havasu, Lake

Pollutant:	Total Petroleum Hydrocarbons as Diesel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under sections 3.1 and 3.6 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess Total Petroleum Hydrocarbons as Diesel consistent with Listing Policy sections 3.1 and 3.6. Total Petroleum Hydrocarbons as Diesel is used to refer to the dissolved fractions of Diesel Range Organics. No evaluation guidelines for the dissolved or sediment fractions of Total Petroleum Hydrocarbons as Diesel for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. Because there are no appropriate evaluation guidelines, staff are unable to make a Listing decision. Based on the readily available data and information, the weight of evidence indicates that there is insufficient justification for placing these water segment-pollutant combinations on the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. No evaluation guidelines for the dissolved or sediment fractions of Total Petroleum Hydrocarbons as Diesel for the protection of human, animal or aquatic life in fresh waters could be found that meet the requirements of section 6.1.3 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 77194, Total Petroleum Hydrocarbons as Diesel	Region 7
Havasu, Lake

LOE ID:

29533

Pollutant:

Total Petroleum Hydrocarbons as Diesel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two sediment samples were collected and analyzed in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. There shall be no increase in hazardous chemical concentrations found in bottom sediments or aquatic life (CRBRWQCB, 2006).

No evaluation guidelines for the sediment fractions Total Petroleum Hydrocarbons as Diesel, used to refer to the dissolved fractions of Diesel Range Organics (dro), for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two sediment samples were collected. Sediment samples were collected in May and October of 2002.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 77194, Total Petroleum Hydrocarbons as Diesel	Region 7
Havasu, Lake

LOE ID:

29480

Pollutant:

Total Petroleum Hydrocarbons as Diesel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Two water samples were collected in 2002 at 1 location in the interior of the lake (SWAMP, 2006).

Data Reference:

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (CRBRWQCB, 2006).

No evaluation guidelines for Total Petroleum Hydrocarbons as Diesel, used to refer to the dissolved fractions of Diesel Range Organics (dro), for the protection of human, animal or aquatic life in fresh waters could be found that met the requirements of Section 6.1.3 of the Listing Policy.

Objective/Criterion Reference:

Water Quality Control Plan Colorado River Basin, with amendments adopted through June 2006

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from one location in the interior of Lake Havasu.

Temporal Representation:

Two water samples were collected. Water samples were collected twice in 2002. Samples were collected in May and October.

Environmental Conditions:

QAPP Information:

The sampling and analysis portions of this study were conducted in accordance with the SWAMP Quality Assurance Management Plan (QAMP) (Puckett, 2002).

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)