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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name:	Cottonwood Creek between Barrett and Morena Reservoirs
Water Body ID:	CAR9113000020200819034926
Water Body Type:	River & Stream


DECISION ID	105666	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Selenium
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Reason for Delisting:	Delisting due to spatial change or other CalWQA administrative reason
Expected TMDL Completion Date:	2019
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. This waterbody was recently split for assessment purposes and this section of the waterbody is now represented by just one sample. This sample size is not sufficient to determine beneficial use support with the power and confidence of the Listing Policy. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of one sample exceeded the water quality threshold, and this sample size is insufficient to determine beneficial use support with the power and confidence of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are 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 removed from the section 303(d) list because applicable water quality standards for the pollutant 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 105666, Selenium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134564

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 SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Selenium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105666, Selenium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134565

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Maximum Contaminant Level for selenium in the Basin Plan is 0.05 mg/L.

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105648	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105648, Arsenic	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134533

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Arsenic.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

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 0.150 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105648, Arsenic	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134532

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): 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:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105649	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105649, Bifenthrin	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134535

Pollutant:

Bifenthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Bifenthrin does not exceed 0.0006 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105650	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105650, Cadmium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134536

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105650, Cadmium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134538

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Cadmium to protect aquatic life in freshwater. The dissolved Cadmium 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105650, Cadmium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134537

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for cadmium is 0.005 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105633	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105633, Deltamethrin	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

227658

Pollutant:

Deltamethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek between Barrett and Morena Reservoirs to determine beneficial use support and results are as follows: 0 of 1 samples exceed the water quality threshold for Deltamethrin.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

Data for this line of evidence for Cottonwood Creek between Barrett and Morena Reservoirs was collected at 1 monitoring site [Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105663	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. One of one sample exceeds the objective for the COLD beneficial use, and zero of one sample exceeds the objective for the WARM beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of one sample exceeds the objective for COLD and zero of one sample exceeds the objective for WARM, and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using table 3.2. 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105663, Oxygen, Dissolved	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134561

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Diego Basin, Cold Water Habitat Objective, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration for cold water habitats shall not be reduced below 8.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105663, Oxygen, Dissolved	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134560

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, San Diego Basin, Warm Water Habitat Objective, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration for warm water habitats shall not be reduced below 5.0 mg/l at any time.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105644	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105644, Alkalinity as CaCO3	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134525

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

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

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105645	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105645, Aluminum	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134528

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aluminum.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105645, Aluminum	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134526

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aluminum.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The California Secondary MCL for aluminum is 0.2 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105645, Aluminum	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134527

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 SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aluminum.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The National Recommended Water Quality Critiera for the protection of aquatic life from aluminum is the chronic continuous concentration (expressed as a 4-day average) of 87 ug/L.

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105631	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Benthic Community Effects
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	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. One line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/are available in the administrative record to assess this indicator. Zero of one benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. These data indicate that the waterbody is likely unimpaired for Benthic Community Effects and therefore no other pollutant LOEs need be associated with this decision at this time. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this waterbody segment 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. Zero of one benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. Therefore, this water body is not exceeding the water quality threshold for the protection of the COLD beneficial use. The available information indicates that the waterbody/pollutant combination should not be placed on the 303(d) List of impaired waters at this time. 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 105631, Benthic Community Effects	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134585

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

One sample was collected at one station on Cottonwood Creek (911HU). The CSCI score for this site is above the 0.79 threshold, and is therefore not exceeding the water quality objective for the aquatic life beneficial use.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

Region 9 CSCI Scores & Water Body Information

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

The sample station: 911S04086

Temporal Representation:

The sample was collected 2009.

Environmental Conditions:

QAPP Information:

Samples were collected for the SWAMP RWB9 Stormwater Monitoring Council CY 2009 following SWAMP protocols and stored in the SWAMP database.

QAPP Information Reference(s):

RWB9 Stormwater Monitoring Council CY 2009

QAPP Information Reference(s):

e-mail clarifying QAPP information


DECISION ID	105652	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105652, Chloride	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134542

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chloride.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Chloride objective for the protection of aquatic life according to Table 3-2 for Cottonwood Creek (Tijuana River watershed) within the Tijuana Hydrologic Unit is 250 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105652, Chloride	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134541

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chloride.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The recommended secondary maximum contamination level acceptable to consumers of drinking water is 250 mg/L.

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 Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105654	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Chromium
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105654, Chromium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134546

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium. Since the chromium species was not identified, the data point(s) were assessed using both the Chromium III criteria which is hardness-dependent, and the criterion continuous concentration (4-day average) to protect aquatic life in freshwater for chromium VI which is 11 ug/L and is not hardness dependent.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved chromium to protect aquatic life in freshwater. The dissolved Chromium 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105654, Chromium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134544

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105654, Chromium	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134545

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for total chromium is 0.05 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105655	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105655, Copper	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134549

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved copper to protect aquatic life in freshwater. The dissolved copper 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105655, Copper	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134548

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Secondary MCL for copper is 1.0 mg/L (Title 22 California Code of Regulations).

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 Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105655, Copper	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134547

Pollutant:

Copper

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105657	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Cyfluthrin
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105657, Cyfluthrin	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134552

Pollutant:

Cyfluthrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of lambda-cyhalothrin does not exceed 0.0005 ug/L and if the 1-h average concentration does not exceed 0.001 ug/L. Mixtures of lambda-cyhalothrin and other pyrethroids should be considered in an additive manner. (Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105658	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Cyhalothrin, Lambda
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105658, Cyhalothrin, Lambda	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134553

Pollutant:

Cyhalothrin, Lambda

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of Cyhalothrin, lambda, total does not exceed 0.0005 ug/L.

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105632	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Cypermethrin
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105632, Cypermethrin	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134508

Pollutant:

Cypermethrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

One of one sample result was not used in the assessment because the laboratory data was non-detect and the method detection limit was above the guideline and therefore the results could not be quantified with the level of certainty required by the Listing Policy

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of cypermethrin does not exceed 0.0002 ug/L and if the 1-h average concentration does not exceed 0.001 ug/L. Fojut et al. 2012)

Guideline Reference:

Aquatic life water quality criteria derived via the UC Davis method: ll. Pyrethroid insecticides. Reviews of Environmental Contamination and Toxicology 216:51-103.

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105636	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Esfenvalerate/Fenvalerate
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105636, Esfenvalerate/Fenvalerate	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134512

Pollutant:

Esfenvalerate/Fenvalerate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

According to the USEPA Office of Pesticide Programs Ecotoxicity database, the aquatic life EC50 for Esfenvalerate/Fenvalerate is 0.9 ug/L.

Guideline Reference:

OPP Pesticide Ecotoxicity Database.

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105637	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Fenpropathrin
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105637, Fenpropathrin	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

227659

Pollutant:

Fenpropathrin

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).

Guideline Reference:

OPP Aquatic Life Benchmarks

Spatial Representation:

Data for this line of evidence for Cottonwood Creek between Barrett and Morena Reservoirs was collected at 1 monitoring site [Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105638	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Iron
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105638, Iron	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134515

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Iron.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Secondary MCL for iron is 0.3 mg/L (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105638, Iron	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134516

Pollutant:

Iron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Iron.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Iron objective for the protection of aquatic life according to Table 3-2 for Cottonwood Creek (Tijuana River watershed) within the Tijuana Hydrologic Unit is 0.3 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105639	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105639, Lead	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134517

Pollutant:

Lead

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105639, Lead	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134518

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved lead to protect aquatic life in freshwater. The dissolved lead 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105642	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105642, Manganese	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134523

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Manganese.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Secondary MCL for manganese is 0.05 mg/L (Water Quality Control Plan for the San Diego Basin).

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 Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105642, Manganese	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134522

Pollutant:

Manganese

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 SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Manganese.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Manganese objective for the protection of aquatic life according to Table 3-2 for Cottonwood Creek (Tijuana River watershed) within the Tijuana Hydrologic Unit is 0.05 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105643	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105643, Nickel	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134554

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nickel is 0.1 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105643, Nickel	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134524

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105643, Nickel	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134555

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Nickel to protect aquatic life in freshwater. The dissolved Nickel 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105659	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105659, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134556

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10.0 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105661	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105661, Nitrogen, Nitrite	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134558

Pollutant:

Nitrogen, Nitrite

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrite (as N) is 1.0 mg/L (Title 22 of the California Code of Regulations).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105646	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Nitrogen, ammonia (Total 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)(2018)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105646, Nitrogen, ammonia (Total Ammonia)	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134530

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Basin Plan: No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

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

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105646, Nitrogen, ammonia (Total Ammonia)	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134529

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Aquatic Life Ambient Water Quality Criteria for Ammonia – Freshwater (USEPA 2013): the 30-day rolling average concentration (criterion continuous concentration or CCC) of total ammonia nitrogen(in mg TAN/L) in freshwater are not to be exceeded more than once every three years on average. The CCC values are based on pH and temperature. The CCC formula is found on page 46 and the table of CCC values is on page 49.

Guideline Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105667	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105667, Silver	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134566

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Silver.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The California Secondary MCL for silver is 0.1 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105667, Silver	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134567

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Silver.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Silver to protect aquatic life in freshwater. The dissolved Silver 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105668	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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)(2018)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105668, Specific Conductivity	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134568

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105669	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105669, Sulfates	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134570

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Sulfate.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Sulfate objective for the protection of aquatic life according to Table 3-2 for Cottonwood Creek (Tijuana River watershed) within the Tijuana Hydrologic Unit is 250 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105669, Sulfates	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134569

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Sulfate.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The California Secondary MCL for sulfate is 250 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105670	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

Pollutant:	Temperature, water
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	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105670, Temperature, water	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134571

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5°F above the natural receiving water temperature.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105671	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105671, Total Dissolved Solids	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134573

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

The California Secondary MCL for Dissolved Solids is 500 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105671, Total Dissolved Solids	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134574

Pollutant:

Total Dissolved Solids

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Dissolved Solids objective for the protection of aquatic life according to Table 3-2 for Cottonwood Creek (Tijuana River watershed) within the Tijuana Hydrologic Unit is 500 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105672	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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)(2018)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105672, Toxicity	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134575

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

One sample was collected to evaluate water toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and reproduction of Ceriodaphnia dubia. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Region 9 Basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL, Significant compared to negative control based on statistical test, less than stated alpha level, AND less than the evaluation threshold (both criteria are met).

Guideline Reference:

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

Guideline Reference:

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

Guideline Reference:

SWAMP_Memo_Toxicity_Data_Intrepretation

Spatial Representation:

The sample was collected at station 911S04086.

Temporal Representation:

The sample was collected in May 2009.

Environmental Conditions:

QAPP Information:

Data quality is good. Data results were recorded in the SWAMP database and followed SWAMP protocols.

QAPP Information Reference(s):


DECISION ID	105673	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105673, Turbidity	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134576

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the San Diego Basin (SDRWQCB 2007): Table 3-2 lists objectives by Hydrologic Unit, Hydrologic Area, and Hydrologic Sub-area. The Turbidity(NTU) objective for the protection of aquatic life according to Table 3-2 for Cottonwood Creek (Tijuana River watershed) within the Tijuana Hydrologic Unit is 20 NTU.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105674	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105674, Zinc	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134580

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Zinc to protect aquatic life in freshwater. The dissolved Zinc 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:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105674, Zinc	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134578

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual chemical or combination of chemicals shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan for the San Diego Basin).

Objective/Criterion Reference:

Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22

Evaluation Guideline:

The California Secondary MCL for zinc is 5.0 mg/L (Title 22 California Code of Regulations).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan

Line of Evidence (LOE) for Decision ID 105674, Zinc	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134577

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).

Guideline Reference:

Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan


DECISION ID	105665	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 105665, pH	Region 9
Cottonwood Creek between Barrett and Morena Reservoirs

LOE ID:

134563

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Cottonwood Creek (Tijuana River watershed) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for pH.

Data Reference:

RWB9 Stormwater Monitoring Council CY 2009

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for Cottonwood Creek (Tijuana River watershed) was collected at 1 monitoring site [ Cottonwood Creek ~0.7mi below Hauser Cr. - 911S04086]

Temporal Representation:

Data was collected on a single day 5/6/2009.

Environmental Conditions:

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

QAPP Information:

The SWAMP QAPP (2008) was followed.

QAPP Information Reference(s):

Surface Water Ambient Monitoring Program Quality Assurance Program Plan