Final California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name:	Wadsworth Canal
Water Body ID:	CAR5203000020041130173733
Water Body Type:	River & Stream


DECISION ID	122347	Region 5
Wadsworth Canal

Pollutant:	Alkalinity as CaCO3
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122347, Alkalinity as CaCO3	Region 5
Wadsworth Canal

LOE ID:

199327

Pollutant:

Alkalinity as CaCO3

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)

Evaluation Guideline:

Alkalinity as CaCO3 levels were assessed for the protection of freshwater aquatic life by comparison to the Evaluation Guideline value of 20,000 ug/L (4 day average) (National Recommended Water Quality Criteria, 2009).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122349	Region 5
Wadsworth Canal

Pollutant:	Aluminum
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122349, Aluminum	Region 5
Wadsworth Canal

LOE ID:

199432

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 STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Aluminum.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Aluminum levels were assessed for the protection of freshwater aquatic life by comparison to the Evaluation Guideline value of 87 ug/L (4 day average) (National Recommended Water Quality Criteria, 2009).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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 122349, Aluminum	Region 5
Wadsworth Canal

LOE ID:

199512

Pollutant:

Aluminum

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Aluminum.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain chemical constituents in concentrations that adversely affect beneficial uses.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122338	Region 5
Wadsworth Canal

Pollutant:	Arsenic
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122338, Arsenic	Region 5
Wadsworth Canal

LOE ID:

199634

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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:

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:

The samples were collected at 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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 122338, Arsenic	Region 5
Wadsworth Canal

LOE ID:

199727

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Arsenic.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122339	Region 5
Wadsworth Canal

Pollutant:	Cadmium
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122339, Cadmium	Region 5
Wadsworth Canal

LOE ID:

200252

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Cadmium.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122348	Region 5
Wadsworth Canal

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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122348, Chromium	Region 5
Wadsworth Canal

LOE ID:

200844

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 STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Chromium.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122340	Region 5
Wadsworth Canal

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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the listing status for this water body-pollutant combination should not change this cycle because of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

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 122340, Copper	Region 5
Wadsworth Canal

LOE ID:

23220

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Five samples were taken from Wadsworth Canal in 2006. One of the five samples exceed guidelines for dissolved copper.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Criteria (USEPA) - Freshwater Aquatic Life ProtectionContinuous Concentration (4-day Average) calculated based on the fallowing formula (e{.8545xLN[hardness]}-1.702)x(0.960) which incorporates hardnessU.S. Environmental Protection Agency, Federal Register, Volume 65, No. 97 (Thursday, 18 May 2000), pp. 31682-31719 [California Toxics Rule]; and Federal Register, Volume 66, No. 30 (Tuesday, 13 February 2001), pp. 9960-9962 [California Toxics Rule Correction] http://www.gpoaccess.gov/fr/browse.html.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected between March and September 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 122340, Copper	Region 5
Wadsworth Canal

LOE ID:

200989

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Copper.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122341	Region 5
Wadsworth Canal

Pollutant:	Iron
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122341, Iron	Region 5
Wadsworth Canal

LOE ID:

202316

Pollutant:

Iron

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-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.

Objective/Criterion Reference:

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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 122341, Iron	Region 5
Wadsworth Canal

LOE ID:

202196

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 STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Iron.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-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.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122342	Region 5
Wadsworth Canal

Pollutant:	Lead
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the listing status for this water body-pollutant combination should not change this cycle because of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

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 122342, Lead	Region 5
Wadsworth Canal

LOE ID:

23216

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

5 samples were taken from Wadsworth Canal between March 2005 and September 2006. 0 of the 5 samples exceeds guidelines for dissolved lead.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Criteria (USEPA) - Freshwater Aquatic Life ProtectionContinuous Concentration (4-day Average) calculated based on the following formula(e(1.273xLN(hardness))-4.705)x((1.46203-LN(hardness))x0.145712)U.S. Environmental Protection Agency, Federal Register, Volume 65, No. 97 (Thursday, 18 May 2000), pp. 31682-31719 [California Toxics Rule]; and Federal Register, Volume 66, No. 30 (Tuesday, 13 February 2001), pp. 9960-9962 [California Toxics Rule Correction] http://www.gpoaccess.gov/fr/browse.html.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Wadsworth Canal at South Butte Rd

Temporal Representation:

Samples were collected between March 2005 and September 2006. Samples were collected at monthly intervals.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 122342, Lead	Region 5
Wadsworth Canal

LOE ID:

202208

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Lead.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	128270	Region 5
Wadsworth Canal

Pollutant:	Mercury
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 128270, Mercury	Region 5
Wadsworth Canal

LOE ID:

202543

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 STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Mercury.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-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 for the Sacramento and San Joaquin River Basins).

Objective/Criterion Reference:

Evaluation Guideline:

National Recommended Water Quality Criteria Continuous Concentrations (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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-09-10 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122343	Region 5
Wadsworth Canal

Pollutant:	Nickel
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122343, Nickel	Region 5
Wadsworth Canal

LOE ID:

202327

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 STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Nickel.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122344	Region 5
Wadsworth Canal

Pollutant:	Selenium
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122344, Selenium	Region 5
Wadsworth Canal

LOE ID:

204762

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 STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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 122344, Selenium	Region 5
Wadsworth Canal

LOE ID:

204730

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Selenium.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122345	Region 5
Wadsworth Canal

Pollutant:	Silver
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122345, Silver	Region 5
Wadsworth Canal

LOE ID:

205014

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:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed STORET data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Silver.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion maximum 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 1 monitoring site (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	122346	Region 5
Wadsworth Canal

Pollutant:	Zinc
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:	Readily available data for this water body have not been used to determine standards attainment. No decision has been made regarding beneficial use support due to a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule. A decision regarding the beneficial use support of this water body will be made during a future Integrated Report cycle if it is determined that this water body is classified as a Water of the United States under the Navigable Waters Protection Rule.

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 of a lack of clarity in the status of this water body under the Clean Water Act and the Navigable Waters Protection Rule.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 122346, Zinc	Region 5
Wadsworth Canal

LOE ID:

207067

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 Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Zinc.

Data Reference:

WQX data for the 2020/2022 integrated report in Region 5.

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 (CALWR_WQX-A5360000)

Temporal Representation:

The samples were collected between the dates of 2014-04-15 and 2015-07-20

Environmental Conditions:

QAPP Information:

STORET

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	72777	Region 5
Wadsworth Canal

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2016)
Revision Status	Original
Sources:	Agriculture
Expected Attainment Date:	2026
Implementation Action Other than TMDL:	This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of chlorpyrifos to this segment have been identified as offsite movement of chlorpyrifos from chlorpyrifos applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This water body - pollutant combination is being considered for removal from the 303(d) list under sections 2.2 and 4.11 of the Listing Policy. No new data or information was available for the 2014 cycle. Under section 4.11, 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. The evidence indicates that chlorpyrifos concentrations are not attaining the applicable water quality standards, but existing pollution control requirements, under State authority, are stringent enough to implement applicable water quality standards because the impairment is being addressed by an enforceable regulatory program, other than a TMDL, that is reasonably expected to result in attainment of the water quality standards within a reasonable, specified time frame. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. Two of 14 available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion. These exceedances occurred more than once every three years. 4. Five of 68 available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion. These exceedances occurred more than once every three years. 5. The sources of chlorpyrifos to this water body segment have been identified as offsite movement of chlorpyrifos from chlorpyrifos applications by the agricultural dischargers, who are regulated under enforceable Waste Discharge Requirements (WDRs). 6. In 2016, the Board adopted Resolution R5-2014-0041 establishing Basin Plan amendments that primarily address the regulation of agricultural pesticide runoff and discharges of diazinon and chlorpyrifos in the Central Valley which are implemented through Board established Waste Discharge Requirements for agricultural dischargers. The amendments established numeric water quality objectives for chlorpyrifos and a control program to ensure that the objectives will be attained within a reasonable, specified time frame. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. 7. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water. 8. The Basin Plan and the Monitoring and Reporting programs in the Boards WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are attained. 9. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.

Regional Board Decision Recommendation:	After review of the available data and information described in the lines of evidence associated with this decision, the Regional Water Board determined that this water body and pollutant combination is still impaired and that it should be listed as being addressed by another regulatory program that is reasonably expected to result in attainment of the water quality standard within a reasonable, specified time frame because an alternative State regulatory program is in place which can be reasonably expected to result in attainment of the water quality standard within a reasonable, specified time frame.

State Board Review of Regional Board Conclusion and Recommendation:	The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for chlorpyrifos as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. 7. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of chlorpyrifos into surface water. 8. The Basin Plan and the Monitoring and Reporting programs in the Boards WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are attained. 9. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.

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 72777, Chlorpyrifos	Region 5
Wadsworth Canal

LOE ID:

23230

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty water samples were collected from Wadsworth Canal from January through March 2004, representing five calculated 4-day average chlorpyrifos concentrations and thirty 1-hour average chlorpyrifos concentrations. Two of the five available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L more than once every three years. Three of the thirty available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average concentration, and 0.025 ug/L as a 1-hour average concentration, not to be exceeded more than once every three years.

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 Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected several times per day during two storm events from January through February 2004 and weekly in March 2004.

Environmental Conditions:

QAPP Information:

Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.

QAPP Information Reference(s):

Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006

Line of Evidence (LOE) for Decision ID 72777, Chlorpyrifos	Region 5
Wadsworth Canal

LOE ID:

23229

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty-eight water samples were collected from Wadsworth Canal from January to February 2003, representing nine calculated 4-day average chlorpyrifos concentrations and thirty-eight 1-hour average chlorpyrifos concentrations. Zero of the nine available 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Two of the thirty-eight available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

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 Wadsworth Canal at South Butte Canal, at South Butte Road.

Temporal Representation:

Samples were collected two to three times per day during two storms in January and February 2003.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	92047	Region 5
Wadsworth Canal

Pollutant:	Diazinon
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2016)
Revision Status	Original
Sources:	Agriculture
Expected Attainment Date:	2026
Implementation Action Other than TMDL:	This water body segment-pollutant combination is being addressed through Basin Plan requirements established under CRWQCB-CVR resolution R5-20140041, and implemented through Board established Waste Discharge Requirements for agricultural discharges. The sources of diazinon to this segment have been identified as offsite movement of diazinon from diazinon applications by the agricultural dischargers regulated by the CRWQCB-CVR WDRs. The Basin Plan identifies numeric water quality objectives for diazinon and chlorpyrifos. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for diazinon as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of diazinon into surface water. The Basin Plan and the Monitoring and Reporting programs in the WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are achieved.
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This water body - pollutant combination is being considered for removal from the 303(d) list under sections 2.2 and 4.11 of the Listing Policy. No new data or information was available for the 2014 cycle. Under section 4.11, 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. The evidence indicates that diazinon concentrations are not attaining the applicable water quality standards, but existing pollution control requirements, under State authority, are stringent enough to implement applicable water quality standards because the impairment is being addressed by an enforceable regulatory program, other than a TMDL, that is reasonably expected to result in attainment of the water quality standards within a reasonable, specified time frame. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. Eighty-seven of 162 available water sample results exceed the water quality objective for aquatic freshwater habitat (WARM or COLD). 4. In addition, twenty-four of 60 available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion. These exceedances occurred more than once every three years. Thirty-two of 145 available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion. These exceedances occurred more than once every three years. 5. The sources of diazinon to this water body segment have been identified as offsite movement of diazinon from diazinon applications by the agricultural dischargers, who are regulated under enforceable Waste Discharge Requirements (WDRs). 6. In 2016, the Board adopted Resolution R5-2014-0041 establishing Basin Plan amendments that primarily address the regulation of agricultural pesticide runoff and discharges of diazinon and chlorpyrifos in the Central Valley which are implemented through Board established Waste Discharge Requirements for agricultural dischargers. The amendments established numeric water quality objectives for diazinon and a control program to ensure that the objectives will be attained within a reasonable, specified time frame. The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for diazinon as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. 7. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of diazinon into surface water. 8. The Basin Plan and the Monitoring and Reporting programs in the Boards WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are attained. 9. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.

Regional Board Decision Recommendation:	After review of the available data and information described in the lines of evidence associated with this decision, the Regional Water Board determined that this water body and pollutant combination is still impaired and that it should be listed as being addressed by another regulatory program that is reasonably expected to result in attainment of the water quality standard within a reasonable, specified time frame because an alternative State regulatory program is in place which can be reasonably expected to result in attainment of the water quality standard within a reasonable, specified time frame.

State Board Review of Regional Board Conclusion and Recommendation:	The Basin Plan and WDRs require growers to implement management practices through the development and implementation of water quality management plans to meet water quality objectives for diazinon as soon as possible but no longer than ten years from the date of approval of the Basin Plan Amendment. These management plans are required to be developed and implemented within one year of the Basin Plan Amendment approval. 7. Agricultural management practices to be implemented may include pest management practices, pesticide application practices, vegetation management practices and water management practices, all of which are effective in reducing offsite movement of diazinon into surface water. 8. The Basin Plan and the Monitoring and Reporting programs in the Boards WDRs require monitoring to determine if adequate reductions are being attained. The Basin Plan and WDRs require management practices to be iteratively improved through updates of the management plans until the water quality objectives are attained. 9. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.

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 92047, Diazinon	Region 5
Wadsworth Canal

LOE ID:

23223

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Fifteen water samples were collected from Wadsworth Canal from January 2005 through September 2006, representing fifteen calculated 4-day average diazinon concentrations and fifteen 1-hour average diazinon concentrations. One of the fifteen available 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the fifteen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Objective/Criterion 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

Evaluation Guideline:

California Department o0f Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average diazinon concentration, and 0.100 ug/L as a 4-day average diazinon concentration, not to be exceeded more than once every three years.

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 Wadsworth Canal from South Butte Road.

Temporal Representation:

Samples were collected monthly from January 2005 through September 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 92047, Diazinon	Region 5
Wadsworth Canal

LOE ID:

23221

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Thirty-five water samples were collected from Wadsworth Canal from January to February 2003, representing seven calculated 4-day average diazinon concentrations and thirty-five 1-hour average diazinon concentrations. Five of the seven available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Seven of the thirty-five available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average diazinon concentration, and 0.100 ug/L as a 4-day average diazinon concentration, not to be exceeded more than once every three years.

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 Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected hourly to daily during two storms in January and February 2003.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 92047, Diazinon	Region 5
Wadsworth Canal

LOE ID:

23222

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Twenty-eight water samples were collected from Wadsworth Canal from January to February 2004, representing ten calculated 4-day average diazinon concentrations and twenty-eight 1-hour average diazinon concentrations. Five of the ten available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Nine of the twenty-eight available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

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 Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected at variable intervals (biweekly and weekly) from January to March 2004.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 92047, Diazinon	Region 5
Wadsworth Canal

LOE ID:

23224

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Sixty-seven water samples were collected from Wadsworth Canal from January 2000 through April 2005, representing twenty-nine calculated 4-day average diazinon concentrations and sixty-seven 1-hour average diazinon concentrations. Thirteen of the twenty-nine available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Sixteen of the sixty-seven available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.

Data Reference:

Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005

Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Objective/Criterion 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

Evaluation Guideline:

California department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average diazinon concentration, and 0.100 ug/L as a 4-day average diazinon concentration, not to be exceeded more than once every three years.

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 Wadsworth Canal at South Butte Road and at Franklin Road.

Temporal Representation:

Samples were collected at variable intervals (e.g., weekly and monthly) from January 2000 through April 2005.

Environmental Conditions:

QAPP Information:

Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm

QAPP Information Reference(s):

Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

Line of Evidence (LOE) for Decision ID 92047, Diazinon	Region 5
Wadsworth Canal

LOE ID:

2675

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

162

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Eighty-seven of 162 samples exceeded the acute guideline (4-day average) (Dileanis et al., 2002; Dileanis, 2003a; Dileanis, 2003b; Gill, 2002; Holmes et al., 2000; Nordmark, 1999; Nordmark, 2000).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

CDFG Hazard Assessment Criteria - 0.10 ug/L 4-day average and 0.16 ug/L 1-hour average (Finlayson, 2004).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Samples were collected at Wadsworth Canal at Franklin Road; in 2000 samples were also collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected in Jan. and Feb (2/day) 1994, 1999, 2000, 2001 and 2002; 2 in Dec. 1998; in 2000 and 2001, 3 samples were collected in March, 3/day in 2002.

Environmental Conditions:

QAPP Information:

Data from USGS reports are considered of adequate quality per section 6.1.4 of the Policy.

QAPP Information Reference(s):


DECISION ID	74711	Region 5
Wadsworth Canal

Pollutant:	Ammonia
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:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data or information was available during the 2014 Integrated Report cycle to reassess this water body segment and pollutant. The decision has not changed. This pollutant was originally considered for listing under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Data is available from one line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. 1. The data used satisfied the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfied the data quantity requirements of section 6.1.5 of the Policy. 3. The recommendation was based on staff findings that 0 of 59 available concentrations exceeded the water quality objective, and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 59 has 5 or more samples that exceed the evaluation criteria. 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 is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data or information was available during the 2014 Integrated Report cycle to reassess this water body segment and pollutant. The decision has not changed.

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 74711, Ammonia	Region 5
Wadsworth Canal

LOE ID:

20991

Pollutant:

Ammonia

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:

Zero of the 59 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Ammonia.

Data Reference:

SWAMP data entered by SWRCB into BDAT database

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Ammonia levels should not exceed 30 mg/L (USEPA Health Advisory).

Guideline Reference:

2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013

Spatial Representation:

Samples were collected at RD777 @ Eager/Larkin Road. Samples were collected at RD777 @ Nuestro Road. Samples were collected at RD777 @ Paseo Ave.. Samples were collected at Wadsworth Canal RD777 @ East Butte Rd.

Temporal Representation:

The samples were collected from Janurary 20, 2000 to March 18, 2002.

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):


DECISION ID	68503	Region 5
Wadsworth Canal

Pollutant:	Methidathion
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:	The decision has not changed. Region 5 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle. 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. Three lines of evidence are available in the administrative record to assess this pollutant. Four of 93 samples exceed the narrative toxicity 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. Four of 93 daily-maximum methidathion concentrations exceeded the Evaluation Guideline of 0.22 ug/L (based on one-tenth the 96-hour LC50 value of 2.2 ug/L for Ceriodapnia dubia, a water flea), and, therefore the four concentrations exceed the narrative toxicity objective. However, 4 of 93 exceedances 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 is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

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 68503, Methidathion	Region 5
Wadsworth Canal

LOE ID:

26206

Pollutant:

Methidathion

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:

Sixtty-six water samples were collected from Wadsworth Canal, representing 50 daily-maximum methidathion concentrations, as reported in the DPR Surface Water Database. Three of the 50 daily-maximum methidathion concentrations exceed the Evaluation Guideline of 0.22 ug/L.

Data Reference:

Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.
The 96-hour LC50 for methidathion for the most sensitive freshwater species tested (Ceriodaphnia dubia, a water flea), is 2.2 ug/L. The Evaluation Guideline is based on one-tenth of the 96-hour LC50 value and, therefore, the Evaluation Guideline value is 0.22 ug/L.

Guideline Reference:

Spatial Representation:

Water samples were collected from Wadsworth Canal at South Butte Road

Temporal Representation:

Water samples were collected from Wadsworth Canal

Environmental Conditions:

QAPP Information:

Data quality: Good. Minimum requirements for the Surface Water Database are:
Name of the sampling agency or organization
Date that each sample was collected
Date of each sample analysis
County where samples were taken
Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.)
Name or description of water body sampled
Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation
Description of analytical QA/QC plan, or statement that no formal plan exists
Additional optional requirements are included on DPR¿s webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm

QAPP Information Reference(s):

Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005

Line of Evidence (LOE) for Decision ID 68503, Methidathion	Region 5
Wadsworth Canal

LOE ID:

26204

Pollutant:

Methidathion

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:

Sixty-three individual water samples were collected from Wadsworth Canal, under the Pesticide TMDL program, in January and February 2003 and between January and March 2004. The 63 individual water samples represent 28 daily maximum methidathion concentrations. One of the 28 daily maximum methidathion concentrations (collected on 28 January 2004) exceeded the Evaluation Guideline of 0.22 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.
The 96-hour LC50 for methidathion for the most sensitive freshwater species tested (Ceriodaphnia dubia , a water flea), is 2.2 ug/L. The Evaluation Guideline is based on one-tenth of the 96-hour LC50 and, therefore the Evaluation Guideline value is 0.22 ug/L.

Guideline Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Guideline Reference:

ECOTOX database, aquatic data. U. S. Environmental Protection Agency

Spatial Representation:

Water samples were collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Water samples were collected from Wadsworth Canal typically during, or around, storm events. Water samples were collected 1, 2, or 3 times per day between January 10 and January 14, 2003 and between February 13 and February 20 2003; on January 31 2004; on February 2, 2004; 1, 2, or 3 times per day between February 15 and February 19, 2004; on February 26, 2004; on March 3, 2004; and on March 10, 2004.

Environmental Conditions:

QAPP Information:

Data Quality: Good. All sampling, analysis and QA/QC protocols are described in a QAPP (Calanchini et al., 2006).

QAPP Information Reference(s):

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

Line of Evidence (LOE) for Decision ID 68503, Methidathion	Region 5
Wadsworth Canal

LOE ID:

26205

Pollutant:

Methidathion

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:

Fifteen water samples were collected from Wadsworth Canal, under the Irrigated Lands Regulatory Program, between January 2005 and September 2006, representing 15 daily-maximum methidathion concentrations. Zero of the 15 water samples contained methidathion at concentrations that exceed the Evaluation Guideline of 0.22 ug/L.

Data Reference:

Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Guideline Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Spatial Representation:

Water samples were collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Water samples were collected from Wadsworth Canal monthly of every two months between January 27, 2005 and September 7, 2005; twice in March 2006; and monthly between May 24, 2006 and September 19, 2006.

Environmental Conditions:

QAPP Information:

Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.

QAPP Information Reference(s):


DECISION ID	74465	Region 5
Wadsworth Canal

Pollutant:	Specific Conductivity
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:	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. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 71 samples exceed the Criteria/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 CWA 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 71 samples exceeded the Criteria/Objective 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:	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:	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 74465, Specific Conductivity	Region 5
Wadsworth Canal

LOE ID:

21072

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:

None of the 69 samples collected by the Surface Water Ambient Monitoring Program exceeded the "recommended" Secondary MCL of 900 uS/cm for electrical conductivity

Data Reference:

SWAMP data entered by SWRCB into BDAT database

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The secondary MCLs for electrical conductivity provide a range of values including a "recommended" level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The ¿recommended¿ concentration was used as it is intended to be protective of all drinking water uses

Objective/Criterion Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from Wadsworth Canal at RD777 and Eager/Larkin Road, at RD777 and Nuestro Road, at RD777 and Paseo Avenue, and at Acacia Road

Temporal Representation:

The samples were collected between December 7, 2000 and April 16 2003

Environmental Conditions:

QAPP Information:

Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 74465, Specific Conductivity	Region 5
Wadsworth Canal

LOE ID:

72128

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 Ag Waiver data for Wadsworth Canal to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Conductivity(Us).

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Wadsworth Canal was collected at 1 monitoring site [Wadsworth Canal at South Butte Road (Weir #4) - 520XWADCN]

Temporal Representation:

Data was collected over the time period 2/11/2007-5/16/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.


DECISION ID	73257	Region 5
Wadsworth Canal

Pollutant:	Toxicity
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:	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. 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 10 samples tested with Ceriodaphnia dubia (an invertebrate species) exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. In addition, none of 8 samples tested with Pimephales promelas (Fathead Minnow, a vertebrate species) exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. Lastly, none of 8 samples tested with Selenastrum capricornutum (an algal species) exceeded the narrative toxicity objective for selenastrum 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 is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

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 73257, Toxicity	Region 5
Wadsworth Canal

LOE ID:

23228

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of 8 samples tested with Selenastrum capricornutum were toxic and violated the narrative toxicity objective.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day chronic-style toxicity tests.

Guideline Reference:

Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-013

Spatial Representation:

All samples were collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected on the following dates: 27 Jan 2005, 19 March 2005, 3 May 2005, 8 June 2005, 7 July 2005, 2 August 2005, 7 September 2005, and 5 October 2005.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Line of Evidence (LOE) for Decision ID 73257, Toxicity	Region 5
Wadsworth Canal

LOE ID:

23217

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 8 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests.

Guideline Reference:

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-821-R-02-012

Spatial Representation:

All samples were collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected on the following dates: 27 Jan 2005, 19 March 2005, 3 May 2005, 8 June 2005, 7 July 2005, 2 August 2005, 7 September 2005, and 5 October 2005.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Line of Evidence (LOE) for Decision ID 73257, Toxicity	Region 5
Wadsworth Canal

LOE ID:

23227

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

None of the 8 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests.

Guideline Reference:

Spatial Representation:

The sample was collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Samples were collected on the following dates: 27 Jan 2005, 19 March 2005, 3 May 2005, 8 June 2005, 7 July 2005, 2 August 2005, 7 September 2005, and 5 October 2005.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012

Line of Evidence (LOE) for Decision ID 73257, Toxicity	Region 5
Wadsworth Canal

LOE ID:

23226

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data is available for a single sample collected on 5 October 2005. The sample, tested with Hyalella azteca, was toxic and violated the narrative toxicity objective. The mean percent survival was 83.75, which represented 88% of the control.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control sediment using Dunnett's test in 10-day Hyalella azteca sediment toxicity tests. Arcsin squareroot transformation was used when necessary to meet the assumptions of normality and homogeneity of variance. Steel's Many-One Rank Test was used for comparison to control if these assumptions were not met after transformation.

Guideline Reference:

Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064

Spatial Representation:

The sample was collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

The sample was collected on 5 October 2005.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73257, Toxicity	Region 5
Wadsworth Canal

LOE ID:

23218

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Surface water samples were tested with Ceriodaphnia dubia and Hyalella azteca.None of the 2 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective.One additional sample (15 March 2003) was tested and found to be non-toxic, but was tested outside of holding time and therefore is not included in this line of evidence.The single sample (13 February 2003) tested with Hyalella azteca was not toxic and did not violate the narrative toxicity objective.

Data Reference:

SWAMP data entered by SWRCB into BDAT database

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

Statistically significant difference from control using a t-test with 4-day acute-style toxicity tests (USEPA 2002).

Guideline Reference:

Spatial Representation:

All samples were collected from Wadsworth Canal at Acacia Avenue.

Temporal Representation:

Samples were collected on the following dates: 3 Jan 2003, 13 February 2003, and 15 March 2003.

Environmental Conditions:

QAPP Information:

Data quality: Excellent. Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.

QAPP Information Reference(s):


DECISION ID	72478	Region 5
Wadsworth Canal

Pollutant:	Indicator Bacteria
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
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. Two lines of evidence are available in the administrative record to assess this pollutant. Six of the 16 samples exceed the USEPA evaluation guideline for E. coli, an indicator bacterial species. 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 16 water samples exceed the evaluation guideline, 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 72478, Indicator Bacteria	Region 5
Wadsworth Canal

LOE ID:

72129

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:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Ag Waiver data for Wadsworth Canal to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for Escherichia coli.

Data Reference:

Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance
or the interactive effect of multiple substances. Compliance with this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, and biotoxicity tests of appropriate duration or other
methods as specified by the Regional Water Board. (Water Quality Control Plan, Central Valley Region, Sacramento River and San Joaquin River Basins)

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Evaluation Guideline:

The USEPA recommended objective for single sample maximum allowable density of E. coli in freshwater designated beach areas is 235 MPN/100mL.

Guideline Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Spatial Representation:

Data for this line of evidence for Wadsworth Canal was collected at 1 monitoring site [Wadsworth Canal at South Butte Road (Weir #4) - 520XWADCN]

Temporal Representation:

Data was collected over the time period 2/11/2007-5/16/2007.

Environmental Conditions:

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

QAPP Information:

The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.

QAPP Information Reference(s):

Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.

Line of Evidence (LOE) for Decision ID 72478, Indicator Bacteria	Region 5
Wadsworth Canal

LOE ID:

23225

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:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The Sac Valley Water Quality Coalition collected 14 samples from March 2005 to September 2006. Four of the 14 samples exceeded the evaluation objective.

Data Reference:

Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.

Objective/Criterion Reference:

Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed

Objective/Criterion Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Evaluation Guideline:

The USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).

Guideline Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Spatial Representation:

Samples were collected from Wadsworth Canal at South Butte Road.

Temporal Representation:

Sampling occurred from March 2005 to September 2006.

Environmental Conditions:

QAPP Information:

Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)

QAPP Information Reference(s):