# Final 2008 California 303(d)/305(b) Integrated Report

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Stanislaus River, Lower
Water Body ID: | CAR5353000019980817151834
Water Body Type: | River & Stream

DECISION ID | 7504
Pollutant: | Diazinon
Final Listing Decision: | Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (TMDL required list)(2006)
Revision Status | Revised
Sources: | Agriculture
Expected TMDL Completion Date: | 2008
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 4.1 of the Listing Policy. Under section 4.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Five samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification in favor removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 115 available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion, and this does not exceed criterion more than once every three years. 4. Five of 197 available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion. These exceedances ocurred more than once every three years. Therefore, according to Section 4.11 of the LIsting Policy, the 303(d) listing for diazinon in the Stanisluas River should not be removed.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7504

LOE ID: | 23333
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 6
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Twenty-three water samples were collected from the loewr Stanislaus River from January through March 2005, representing six calculated 4-day average diazinon concentrations and twenty-three 1-hour average diazinon concentrations. One of the six available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Four of the twenty-three available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average diazinon concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected either hourly, daily, or weekly between January and March 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23332
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fourteen water samples were collected from the Stanislaus River from March to August 2004, representing fourteen calculated 4-day average diazinon concentrations and fourteen 1-hour average diazinon concentrations. Zero of the fourteen available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the fourteen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at variable intervals (weekly or every two weeks) from March to August 2004.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23316
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Seventeen water samples were collected from the lower Stanislaus River from January to March 2003, representing five calculated 4-day average diazinon concentrations and seventeen 1-hour average diazinon concentrations. Zero of the five available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.10 ug/L. Zero of the seventeen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.16 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at variable intervals (hourly or daily) from January to March 2003.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23317
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 19
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Nineteen water samples were collected from the lower Stanislaus River from March to August 2003, representing nineteen calculated 4-day average diazinon concentrations and nineteen 1-hour average diazinon concentrations. Zero of the nineteen available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the nineteen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at variable intervals (twice per week or weekly) from March through August 2003.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23352
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 41
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Sixty-three water samples were collected from the Stanislaus River from January 2000 through August 2001, representing forty-one calculated 4-day average diazinon concentrations and sixty-three 1-hour average diazinon concentrations. Zero of the forty-one available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon crierion of 0.100 ug/L. Zero of the sixty-three available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
| Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park and near Ripon.
Temporal Representation: | Samples were collected at variable intervals (e.g. weekly, monthly) from January 2000 through August 2001.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
LOE ID: | 4562
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: | Placeholder reference pre-2006 303(d)
Water Quality Objective/Criterion: | Unspecified
Objective/Criterion Reference: | Placeholder reference pre-2006 303(d)
Evaluation Guideline: | Unspecified
Guideline Reference: | Placeholder reference pre-2006 303(d)
Spatial Representation: | Unspecified
Temporal Representation: | Unspecified
Environmental Conditions: | Unspecified
QAPP Information: | Unspecified
QAPP Information Reference(s):
LOE ID: | 23334
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fourteen water samples were collected from the Stanislaus River from March through August 2005, representing fourteen calculated 4-day average diazinon concentrations and fourteen 1-hour average diazinon concentrations. Zero of the fourteen available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the fourteen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L as a 4-day average diazinon concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected weekly from March 10, 2005 through March 31, 2005, and from June 29, 2005 to August 31, 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23335
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Thirty water samples were collected from the lower Stanislaus River from January through August 2006, representing fourteen calculated 4-day average diazinon concentrations and thirty 1-hour average diazinon concentrations. Zero of the fourteen available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. Zero of the thirty available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Diazinon Criteria: 0.160 ug/L as a 1-hour average concentration, and 0.100 ug/L 4-day average concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected weekly between January and August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23318
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Eighteen water samples were collected from the lower Stanislaus River in February 2004, representing two calculated 4-day average diazinon concentrations and eighteen 1-hour average diazinon concentrations. Zero of the two available calculated 4-day average diazinon concentrations exceeded the 4-day average diazinon criterion of 0.100 ug/L. One of the eighteen available 1-hour average diazinon concentrations exceeded the 1-hour average diazinon criterion of 0.160 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Fish and Game Hazard Assessment Criteria - 0.160 ug/L 1-hour average, and 0.100 ug/L 4-day average diazinon concentrations, not to be exceeded more than once every three years (Siepmann and Finlayson, 2000 and Finlayson, 2004).
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected hourly and daily during two storm events in February 2004.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006

DECISION ID | 7507
Pollutant: | Unknown Toxicity
Final Listing Decision: | Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (TMDL required list)(2006)
Revision Status | Revised
Sources: | Source Unknown
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for removal from the 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. Three lines of evidence are available in the administrative record to assess pollutant. Four of samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Four of 11 samples tested with fathead minnow (chronic toxicity tests) exceeded the narrative toxicity objective and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. In addition, 0 of 13 samples tested with fathead minnow (acute toxicity tests) exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. Lastly, 0 of 11 samples tested with ceriodaphnia (acute toxicity tests) exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7507

LOE ID: | 25069
Pollutant: | Unknown Toxicity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 13
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Zero of the 13 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Unknown Toxicity-Pimephales promelas.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | Statistically significant difference from control using a Fishers Exact analysis with 96-hour acute-style toxicity tests.
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
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from Oct 26 2000 to Nov 20 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
LOE ID: | 25071
Pollutant: | Unknown Toxicity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 11
Number of Exceedances: | 4
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | 4 of the 11 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Unknown Toxicity-Pimephales promelas.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | Statistically significant difference from control using a Fishers Exact analysis with 7-day chronic toxicity tests.
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
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from Nov 22 2004 to Nov 29 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
LOE ID: | 4565
Pollutant: | Unknown Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: | Placeholder reference pre-2006 303(d)
Water Quality Objective/Criterion: |
Objective/Criterion Reference:
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Unspecified
Temporal Representation: | Unspecified
Environmental Conditions: | Unspecified
QAPP Information: | Unspecified
QAPP Information Reference(s):
LOE ID: | 25072
Pollutant: | Unknown Toxicity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 11
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Zero of the 11 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Unknown Toxicity-Ceriodaphia dubia.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | Statistically significant difference from control using a Fishers Exact analysis with 48-hour acute-style toxicity tests.
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
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from Oct 24 2001 to Nov 20 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7972
Pollutant: | Cadmium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 6 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 17 has 2 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7972

LOE ID: | 6620
Pollutant: | Cadmium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 6
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | None of the 6 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR crioterion of dissolved cadmium
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | Dissolved cadmium levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average dissolved)=(EXP(1.128*LN(hardness)-3.6867))*(1.136672-(LN(hardness)*0.041838))
Objective/Criterion Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell Park
Temporal Representation: | The samples were collected between September 26, 2001 and November 20, 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7973
Pollutant: | Copper
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 12 samples exceed the California Toxics Rule 4-day average criteria for dissolved Copper and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7973

LOE ID: | 6622
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | None of the 12 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Copper.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | California Toxics Rule 4-day average criteria for dissolved Copper.
Objective/Criterion Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from November 2000 to November 2002.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 8107
Pollutant: | Escherichia coli (E. Coli)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under section 3.3 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. Five of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of 70 available concentrations exceeded the USEPA E. Coli Guideline for Water Contact Recreation and this does not exceed the allowable frequency using Table 3.2 of the Listing Policy. In addition, 1 of 70 available concentrations exceeded the USEPA E. Coli Guideline for Non-Contact Recreation and this does not exceed the allowable frequency using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 8107

LOE ID: | 6997
Pollutant: | Escherichia coli (E. Coli)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Non-Contact Recreation
Number of Samples: | 70
Number of Exceedances: | 1
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | One of the 70 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for E.Coli Bacteria. The exceeded results are as follows: 10/21/2003 - a sample taken at Stanislaus River @ Caswell Park had a result of 1120MPN/100mL.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | E.Coli Bacteria levels should not exceed 409 MPN/100 mL in any single sample (USEPA E.Coli Guideline)
Guideline Reference: | Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park. Samples were collected at Stanislaus River @ Knight's Ferry.
Temporal Representation: | The samples were collected from Jul 31 2002 to Nov 29 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
LOE ID: | 6904
Pollutant: | Escherichia coli (E. Coli)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 70
Number of Exceedances: | 5
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Five of the 70 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for E.Coli Bacteria. The exceeded results are as follows: 10/7/2003 - a sample taken at Stanislaus River @ Caswell Park had a result of 344MPN/100mL. 10/21/2003 - a sample taken at Stanislaus River @ Caswell Park had a result of 1120MPN/100mL. 1/6/2004 - a sample taken at Stanislaus River @ Caswell Park had a result of 236MPN/100mL. 10/27/2004 - a sample taken at Stanislaus River @ Caswell Park had a result of 299MPN/100mL. 12/28/2004 - a sample taken at Stanislaus River @ Caswell Park had a result of 308MPN/100mL.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | E.Coli Bacteria levels should not exceed 235 MPN/100 mL in any single sample (USEPA E.Coli Guideline)
Guideline Reference: | Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park. Samples were collected at Stanislaus River @ Knight's Ferry.
Temporal Representation: | The samples were collected from Jul 31 2002 to Nov 29 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7976
Pollutant: | Lead
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 13 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 35 has 3 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7976

LOE ID: | 6627
Pollutant: | Lead
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 13
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Zero of the 13 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved lead
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | Dissolved lead levels should not exceed the calculated CTR value based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(1.273*LN(hardness)-1.46))*(1.46203-(LN(hardness)*0.145712))
Objective/Criterion Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell Park
Temporal Representation: | The samples were collected between November 29, 2000 and November 20, 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7978
Pollutant: | Nickel
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 13 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 34 has 3 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7978

LOE ID: | 6634
Pollutant: | Nickel
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 13
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Zero of the 13 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved nickel
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | Dissolved nickel levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.846*LN(hardness)+2.255))*(0.998)
Objective/Criterion Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell Park
Temporal Representation: | The samples were collected between November 29, 2000, and November 20, 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7979
Pollutant: | Nitrate as Nitrate (NO3)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 9 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 9 has 2 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7979

LOE ID: | 6636
Pollutant: | Nitrate as Nitrate (NO3)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 9
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | 0 of the 9 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Nitrate-N.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | Nitrate-N levels should not to exceed 100 mg/L (USEPA National Ambient Water Quality Objective)
Guideline Reference: | National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology. 4304T The Blue Book
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from Jun 29 2000 to Mar 28 2001
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7974
Pollutant: | Oxygen, Dissolved
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | "This pollutant is being considered for listing under sections 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 92 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.2 of the Listing Policy. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. "
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7974

LOE ID: | 6624
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 92
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | 0 of the 92 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Dissolved Oxygen.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | The Basin Plan Objective sets the minimum Dissolved Oxygen content at 7 mg/L
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from Nov 29 2000 to Nov 20 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7980
Pollutant: | Selenium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 64 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 64 has 6 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7980

LOE ID: | 6637
Pollutant: | Selenium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 64
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | 0 of the 64 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Selenium.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006) Selenium levels should not to exceed 5 ug/L (CTR)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park.
Temporal Representation: | The samples were collected from Jan 28 1998 to Nov 29 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7981
Pollutant: | Zinc
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 2 lines of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 12 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 33 has 3 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7981

LOE ID: | 6639
Pollutant: | Zinc
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Zero of the 12 samples collected by the Surface Water Ambient Monitoring Program exceeded the calculated CTR CMC for dissolved zinc
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | Dissolved zinc levels should not exceed the calculated CTR limit based on the formula: Criteria Maximum Concentration=EXP((0.8473*LN(hardness))+0.884)*(0.978)
Objective/Criterion Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell Park
Temporal Representation: | The samples were collected between November 29, 2000, and November 20, 2002
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 7975
Pollutant: | pH
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for listing under sections 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 3 of 121 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.2 of the Listing Policy. Table 3.2 of the listing policy recommends listing if a sample size of 121 has 20 or more samples that exceed the evaluation criteria. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7975

LOE ID: | 6625
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 121
Number of Exceedances: | 3
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | 3 of the 121 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for pH. The exceeded results are as follows: 12/27/2000 - a sample taken at Stanislaus River @ Caswell Park had a result of 9. 2/21/2001 - a sample taken at Stanislaus River @ Caswell Park had a result of 8.8. 10/27/2004 - a sample taken at Stanislaus River @ Caswell Park had a result of 8.6.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Drainage Basin Inflows
Water Quality Objective/Criterion: | pH levels should not be lower than 6.5 or higher than 8.5 (Basin Plan Objective)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Stanislaus River @ Caswell Park. Samples were collected at Stanislaus River @ Knight's Ferry.
Temporal Representation: | The samples were collected from Jan 28 1998 to Nov 29 2005
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):

DECISION ID | 11952
Pollutant: | Chlorpyrifos
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Agriculture
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. Ten samples exceed the narrative toxicity water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The 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. Ten of one hundred fifty-two available calculated 4-day average chlorpyrifos concentrations, collected between 2000 and 2006, exceeded the 4-day average chlorpyrifos criterion as follows: 2 exceedances in 2001 and 2001; zero exceedances in 2002; 5 exceedances in 2003; zero exceedances in 2004; 2 exceedances in 2005; and 1 exceedance in 2006. Since there are more than one exceedance every three years, in accordance with Section 3.11 of the Listing Policy and with the maximum exceedance frequency associated with the chlorpyrifos criteria, this water body should be put on the 303(d) list for chlorpyrifos. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11952

LOE ID: | 23302
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fourteen water samples were collected from the Stanislaus River from March through August 2005, representing fourteen calculated 4-day average chlorpyrifos concentrations and fourteen 1-hour average chlorpyrifos concentrations. Two of the fourteen available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the fourteen available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at weekly interval from March through March 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23303
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 15
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Twenty-nine water samples were collected from the Stanislaus River from January through August 2006, representing fifteen calculated 4-day average chlorpyrifos concentrations, and twenty-nine 1-hour average chlorpyrifos concentrations. One of the fifteen available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. One of the twenty-nine available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at weekly from January through August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23301
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Sixteen water samples were collected from the Stanislaus River from January through March 2005, representing two calculated 4-day average chlorpyrifos concentrations and sixteen 1-hour average chlorpyrifos concentrations. Zero of the two available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the sixteen available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at variable intervals (hourly, daily, and weekly) from January through March 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23300
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 10
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Ten water samples were collected from the Stanislaus River from March to August 2004, representing ten calculated 4-day average chlorpyrifos concentrations and ten 1-hour average chlorpyrifos concentrations. Zero of the ten available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the ten available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at variable intervals (weekly or biweekly) from March to August 2004.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23315
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 41
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Sixty-three water samples were collected from the Stanislaus River from January 2000 through August 2001, representing forty-one calculated 4-day average chlorpyrifos concentrations and sixty-three 1-hour average chlorpyrifos concentrations. Two of the forty-one available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Two of the sixty-three available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
| Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park, and near Ripon.
Temporal Representation: | Samples were collected at variable intervals (e.g. weekly, monthly) from January 2000 through August 2001.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
LOE ID: | 23181
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 15
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fifty-seven water samples were collected from the Stanislaus River from January to March 2003, representing fifteen calculated 4-day average chlorpyrifos concentrations and fifty-seven 1-hour average chlorpyrifos concentrations. Zero of the fifteen available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Zero of the fifty-seven available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park, at Orange Blossom, and at Jacob Meyer Park.
Temporal Representation: | Samples were collected at variable intervals (hourly or daily) from January to March 2003.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23182
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 53
Number of Exceedances: | 5
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fifty-three water samples were collected from the Stanislaus River from March to August 2003, representing fifty-three calculated 4-day average chlorpyrifos concentrations and seventeen 1-hour average chlorpyrifos concentrations. Five of the fifty-three available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. Two of the fifty-three available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park, at Orange Blossom, and at Jacob Meyer Park.
Temporal Representation: | Samples were collected at variable intervals (biweekly and weekly) from March through August 2003.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006
LOE ID: | 23183
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Eighteen water samples were collected from the Stanislaus River in February 2004, representing two calculated 4-day average chlorpyrifos concentrations and eighteen 1-hour average chlorpyrifos concentrations. Zero of the two available calculated 4-day average chlorpyrifos concentrations exceeded the 4-day average chlorpyrifos criterion of 0.015 ug/L. One of the eighteen available 1-hour average chlorpyrifos concentrations exceeded the 1-hour average chlorpyrifos criterion of 0.025 ug/L.
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Chlorpyrifos Criteria: 0.015 ug/L as a 4-day average chlorpyrifos concentration, and 0.025 ug/L as a 1-hour average chlorpyrifos concentration, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from the Stanislaus River at Caswell State Park.
Temporal Representation: | Samples were collected at variable intervals (hourly and daily) during two storm events in February 2004.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Calanchini, H. 2006. Quality Assurance Project Plan, Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. John Muir Institute of the Environment, U.C. Davis. Davis, CA.
QAPP Information Reference(s): | Quality Assurance Project Plan. Sacramento and San Joaquin River Basins and Sacramento-San Joaquin Delta TMDL Monitoring for Organophosphorus Pesticides and Other Pesticides Identified as Posing a High Risk to Surface Waters. Final. SWAMP Project ID 02TM5001 (Revision 0.0). John Muir Institute of the Environment, U.C. Davis. Davis, CA. January 26, 2006

DECISION ID | 15206
Pollutant: | Temperature, water
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Source Unknown
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy (Policy). Six lines of evidence are available in the administrative record to assess this pollutant. These are temperature data on five life stages for anadromous fish and information on the historical and current state of the fishery. A large number of seven-day averages of maximum (7DADM) daily temperatures exceeded the anadromous fish life stage temperature criteria. Based on readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 f the Policy. 3. Thirty-eight of 76 yearly maximum 7DADM values calculated from temperature data collected during the adult migration life stage (Julian weeks 36 through 43) from 1991 to 2007 exceeded the narrative temperature objective, and this exceeds the minimum criteria for listing from Table 3.2 of the Policy. 4. Thirty-eight of 49 yearly maximum 7DADM values calculated from temperature data collected during the spawning life stage (Julian weeks 40 through 50) from 1999 to 2007 exceeded the narrative temperature objective, and this exceeds the minimum criteria for listing from Table 3.2 of the Policy. 5. Thirty-six of 73 yearly maximum 7DADM values calculated from temperature data collected during the smoltification life stage (Julian weeks 11 through 24) from 1999 to 2007 exceeded the narrative temperature objective, and this exceeds the minimum criteria for listing from Table 3.2 of the Policy. 6. Thirty-six of 73 yearly maximum 7DADM values calculated from temperature data collected during the juvenile rearing life stage (Julian weeks 11 through 24) from 1999 to 2007 exceeded the narrative temperature objective, and this exceeds the minimum criteria for listing from Table 3.2 of the Policy. 7. Seven of 27 yearly maximum 7DADM values calculated from temperature data collected during the steelhead summer rearing life stage (Julian weeks 24 through 37) from 1999 to 2007 exceeded the narrative temperature objective, and this exceeds the minimum criteria for listing from Table 3.2 of the Policy. 8. Pursuant to section 3.11 of the Policy, no additional data and information are available indicating that standards are not met. 9. The data used satisfies the data quality requirements of section 6.1.4.5.7 of the Policy.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB-CVR staff concludes that the water body pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 15206

LOE ID: | 26528
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Fish Migration
Number of Samples: | 73
Number of Exceedances: | 36
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Stream temperatures were measured by CDFG using data loggers (Stowaways, Tidbits and Hobo Temp Pros). Monitoring occurred from 1999 to 2007 depending on the monitoring station, identified by a river mile. The 7DADM was recorded weekly for each river mile. The maximum 7DADM value was calculated for each year. Based on the data provided, 36 out of 73 maximum 7DADM values exceeded the <16 degrees C criteria from 1999 to 2007.
Data Reference: | Cover letter, data and information regarding elevated water temperatures in the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
| Access and DSS database files of water temperature data, one each for the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
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 Water Board that such alteration in temperature does not adversely affect beneficial uses. In determining compliance with the water quality objectives for temperature, appropriate averaging periods may be applied provided that beneficial uses will be fully protected. (Central Valley Regional Board Basin Plan, Pg. III-8.00, Water Quality Objectives)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The guideline used was the 2003 US EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards (USEPA, 2003). The document includes recommended temperature criteria for salmon and trout based on different life stages. The recommended temperature for salmon and trout smoltification is <16 degrees C for a 7DADM. The smoltification life stage occurs from river mile 58 (Goodwin Dam) to river mile 0 (confluence with the San Joaquin River). This life stage occurs during Julian weeks 11 to 24, which is approximately March 15th through June 15th.
Guideline Reference: | EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. U.S. Environmental Protection Agency Region 10 Office of Water, Seattle, WA.
Spatial Representation: | The smoltification life stage occurs from river mile 58 (Goodwin Dam) to river mile 0 (confluence with the San Joaquin River). Stream temperatures were monitored at the following stream locations during the smoltification life stage: River Miles 58 (Goodwin Dam), 54 (Sonora Road Bridge), 46 (Orange Blossom Bridge), 40 (Oakdale Recreation Area), 38 (Gambini property), 34 (Army Corps of Engineers property), 33 (Jacob Meyers Park), 31 (Army Corps of Engineers property), 29 (McHenry Access), 19 (above MID Spill), 15 (Hwy 99), and 0 (confluence with the San Joaquin River).
Temporal Representation: | The smoltification life stage occurs during Julian weeks 11 to 24, which is approximately March 15th through June 15th. Data was collected during this life stage on a continuous basis (hourly intervals) from 1999 to 2007, depending on the station and year monitored. Refer to the CDFG 2007 report (Gordus, 2007) for specific years for each location.
Environmental Conditions: |
QAPP Information: | Data is supported by a Quality Assurance Project Plan (QAPP) pursuant to the requirements of 40 CFR 31.45 and are acceptable for use in developing the section 303(d) list.
QAPP Information Reference(s):
LOE ID: | 26531
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Aquatic Life Use: | Fish Migration
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | QUALITATIVE (EVALUATED) ASSESSMENT - UNSPECIFIED
Data Used to Assess Water Quality: | The Stanislaus has a good spring and fall-run of salmon (G.H. Clark, 1929). Prior to Tulloch Dam (1958) the average annual fall-run escapement averaged 10,300 spawners (Yoshiyama, Ronald M., Eric R. Gerstun, Frank W. Fisher, and Peter. B. Moyle, 2001). Post Tulloch, escapement declined to an average of 4,300 spawners. After New Melones Reservoir was operating in the 1970s, annual escapement dropped to an average of 3,600 spawners. Since 2000, the escapement population has steadily declined and by 2006 had dropped to about 65% below the year 2000 peak population. Also, populations have declined when Delta exports and ocean harvesting was reduced at the same time (CDFG July 2007 Letter to the Federal Energy Regulatory Commission). Between 1952 and 2006 the fall-run escapement population has oscillated over time and has dropped to levels less than 1,000 on several occasions. The Department of Fish and Game has submitted data to the Regional Water Quality Control Board regarding warm water temperatures present in the lower Stanislaus River during the fall adult upstream migration seasons for the years 1999 thru 2006 (Tables 7 and 10 in CDFGs Letter to the RWQCB, 2007). Also, the Department of Fish and Game has submitted data to the Regional Water Quality Control Board regarding warm water temperatures present in the lower Stanislaus River spawning habitat reaches during the first half of the spawning season for years 1999 thru 2005 (Table 11 in CDFGs Letter to the RWQCB, 2007). Data collected in 2002 at Orange Blossom Bridge shows as water temperature decreased below 13 degrees C, spawning activity, measured by weekly spawning redd counts, rises (Jason Guignard, 2002). Steelhead in the Stanislaus are considered winter run. Adult steelhead have been recently captured while migrating upstream at the fish counting weir located near Riverbank (Cramer Fish Sciences) Juvenile rainbow trout have been caught in rotary screw traps out-migrating the Stanislaus River. Anecdotal reports by anglers suggest that steelhead populations are good following years where summer rearing conditions are good (e.g. presence of cold water temperatures). State and Federal agencies believe their abundance trends mirrors those of salmon causing them to be listed as threatened in the Central Valley. The Department of Fish and Game submitted data to the Regional Water Quality Control Board regarding warm water temperatures present in the lower Stanislaus River juvenile steelhead rearing reaches during the summer for years 1999 thru 2006 (Table 11 in CDFGs Letter to the RWQCB, 2007).
Data Reference: | Cover letter, data and information regarding elevated water temperatures in the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
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 Water Board that such alteration in temperature does not adversely affect beneficial uses. In determining compliance with the water quality objectives for temperature, appropriate averaging periods may be applied provided that beneficial uses will be fully protected. (Central Valley Regional Board Basin Plan, Pg. III-8.00, Water Quality Objectives)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | In the absence of necessary data to interpret numeric water quality objectives, recent temperature monitoring data shall be compared to the temperature requirements of aquatic life in the water segment. In many cases, fisheries, particularly salmonids, represent the beneficial uses most sensitive to temperature. Information on current and historic conditions and distribution of sensitive beneficial uses (e.g., fishery resources) in the water segment is necessary, as well as recent temperature data reflective of conditions experienced by the most sensitive life stage of the aquatic life species. If temperature data from past (historic) periods corresponding to times when the beneficial use was fully supported are not available, information about presence/absence or abundance of sensitive aquatic life species shall be used to infer past (historic) temperature conditions if loss of habitat, diversions, toxic spills, and other factors are also listed. (SWRCB, 2004)
Guideline Reference: | Water Quality Control Policy For Developing California's Clean Water Act Section 303(d) List. Sacramento, CA: State Water Resources Control Board, California Environmental Protection Agency.
Spatial Representation: | Stanislaus River.
Temporal Representation: | Information referenced from year 1929 to 2006.
Environmental Conditions: |
QAPP Information: | San Joaquin Fall-Run Chinook Salmon and Steelhead Rainbow Trout Historical Population Trend Summary. Dean Marston. September 2007.
QAPP Information Reference(s):
LOE ID: | 26530
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 27
Number of Exceedances: | 7
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Stream temperatures were measured by CDFG using data loggers (Stowaway, Tidbits and Hobo Temp Pros). Monitoring occurred from 1999 to 2007 depending on the monitoring station, identified by a river mile. The 7DADM was recorded weekly for each river mile. The maximum 7DADM value was calculated for each year. Based on the data provided, 7 out of 27 maximum 7DADM values exceeded the <18 degrees C criteria from 1999 to 2007.
Data Reference: | Cover letter, data and information regarding elevated water temperatures in the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
| Access and DSS database files of water temperature data, one each for the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
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 Water Board that such alteration in temperature does not adversely affect beneficial uses. In determining compliance with the water quality objectives for temperature, appropriate averaging periods may be applied provided that beneficial uses will be fully protected. (Central Valley Regional Board Basin Plan, Pg. III-8.00, Water Quality Objectives)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The guideline used was the 2003 US EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards (USEPA, 2003). The document includes recommended temperature criteria for salmon and trout based on different life stages. The recommended temperature for steelhead summer rearing is <18 degrees C for a 7DADM. The steelhead summer rearing life stage occurs from river mile 58 (Goodwin Dam) to river mile 45. This life stage occurs during Julian weeks 24 through 37, which is approximately June 15th through September 15th.
Guideline Reference: | EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. U.S. Environmental Protection Agency Region 10 Office of Water, Seattle, WA.
Spatial Representation: | The steelhead summer rearing life stage occurs from river mile 58 (Goodwin Dam) to river mile 45. Stream temperatures were monitored at the following stream locations during the steelhead summer rearing life stage: River Miles 58 (Goodwin Dam), 54 (Goodwin Canyon) and 46 (Sonora Road Bridge).
Temporal Representation: | The steelhead summer rearing life stage occurs during Julian weeks 24 through 37, which is approximately June 15th through September 15th. Data was collected during this life stage on a continuous basis (hourly intervals) from 1999 through 2007, depending on the station and year monitored. Refer to the CDFG 2007 report (Gordus, 2007) for specific years for each location.
Environmental Conditions: |
QAPP Information: | Data is supported by a Quality Assurance Project Plan (QAPP) pursuant to the requirements of 40 CFR 31.45 and are acceptable for use in developing the section 303(d) list.
QAPP Information Reference(s):
LOE ID: | 26529
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 73
Number of Exceedances: | 36
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Stream temperatures were measured by CDFG using data loggers (Stowaways, Tidbits and Hobo Temp Pros). Monitoring occurred from 1999 to 2007 depending on the monitoring station, identified by a river mile. The 7DADM was recorded weekly for each river mile. The maximum 7DADM value was calculated for each year. Based on the data provided, 36 out of 73 maximum 7DADM values exceeded the <16 degrees C criteria from 1999 to 2007.
Data Reference: | Cover letter, data and information regarding elevated water temperatures in the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
| Access and DSS database files of water temperature data, one each for the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
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 Water Board that such alteration in temperature does not adversely affect beneficial uses. In determining compliance with the water quality objectives for temperature, appropriate averaging periods may be applied provided that beneficial uses will be fully protected. (Central Valley Regional Board Basin Plan, Pg. III-8.00, Water Quality Objectives)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The guideline used was the 2003 US EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards (USEPA, 2003). The document includes recommended temperature criteria for salmon and trout based on different life stages. The recommended temperature for salmon and trout juvenile rearing is <16 degrees C for a 7DADM. The juvenile rearing life stage occurs from river mile 58 (Goodwin Dam) to river mile 0 (confluence with the San Joaquin River). This life stage occurs during Julian weeks 11 to 24, which is approximately March 25th through June 15th.
Guideline Reference: | EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. U.S. Environmental Protection Agency Region 10 Office of Water, Seattle, WA.
Spatial Representation: | The juvenile rearing life stage occurs from river mile 58 (Goodwin Dam) to river mile 0 (confluence with the San Joaquin River). Stream temperatures monitored at the following stream locations during the juvenile rearing life stage: River Miles 58 (Goodwin Dam), 54 (Sonora Road Bridge), 46 (Orange Blossom Bridge), 40 (Oakdale Recreation Area), 38 (Gambini property), 34 (Army Corps of Engineers property), 33 (Jacob Meyers Park), 31 (Army Corps of Engineers property), 29 (McHenry Access), 19 (above MID Spill), 15 (Hwy 99), and 0 (confluence with the San Joaquin River).
Temporal Representation: | The juvenile rearing life stage occurs during Julian weeks 11 to 24, which is approximately March 15th through June 15th. Data was collected during this life stage on a continuous basis (hourly intervals) from 1999 to 2007, depending on the station and year monitored. Refer to the CDFG 2007 report (Gordus, 2007) for specific years for each location.
Environmental Conditions: |
QAPP Information: | Data is supported by a Quality Assurance Project Plan (QAPP) pursuant to the requirements of 40 CFR 31.45 and are acceptable for use in developing the section 303(d) list.
QAPP Information Reference(s):
LOE ID: | 26527
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Fish Spawning
Number of Samples: | 49
Number of Exceedances: | 38
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Stream temperatures were measured by CDFG using data loggers (Stowaways, Tidbits and Hobo Temp Pros). Monitoring occurred from 1999 to 2007 depending on the monitoring station, identified by a river mile. The 7DADM was recorded weekly for each river mile. The maximum 7DADM value was calculated for each year. Based on the data provided, 38 out of 49 maximum 7DADM values exceeded the <13 degrees C criteria from 1999 to 2007.
Data Reference: | Cover letter, data and information regarding elevated water temperatures in the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
| Access and DSS database files of water temperature data, one each for the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
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 Water Board that such alteration in temperature does not adversely affect beneficial uses. In determining compliance with the water quality objectives for temperature, appropriate averaging periods may be applied provided that beneficial uses will be fully protected. (Central Valley Regional Board Basin Plan, Pg. III-8.00, Water Quality Objectives)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The guideline used was the 2003 US EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards (USEPA, 2003). The document includes recommended temperature criteria for salmon and trout based on different life stages. The recommended temperature for salmon and trout spawning is <13 degrees C for a 7DADM. The spawning life stage occurs from river mile 33 (Jacob Meyers Park) to 58 (Goodwin Dam). This life stage occurs during Julian weeks 40 through 50, which is approximately October 1st through December 15th.
Guideline Reference: | EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. U.S. Environmental Protection Agency Region 10 Office of Water, Seattle, WA.
Spatial Representation: | The spawning life stage occurs from river mile 33 (Jacob Meyers Park) to river mile 58 (Goodwin Dam). Stream temperatures were monitored at the following stream locations during the spawning life stage: River Miles 33 (Jacob Meyer Park), 34 (Army Corp of Engineers property), 38 (Gambini property), 40 (Oakdale Recreation Area), 46 (Orange Blossom Bridge), 54 (Sonora Road Bridge), and 58 (Goodwin Dam).
Temporal Representation: | The spawning life stage occurs during Julian weeks 40 through 50, which is approximately October 1st through December 15th. Data was collected during this life stage on a continuous basis (hourly intervals) from 1991 through 2007, depending on the station and year monitored. Refer to the CDFG 2007 report (Gordus, 2007) for specific years for each location.
Environmental Conditions: |
QAPP Information: | Data is supported by a Quality Assurance Project Plan (QAPP) pursuant to the requirements of 40 CFR 31.45 and are acceptable for use in developing the section 303(d) list.
QAPP Information Reference(s):
LOE ID: | 26231
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Fish Migration
Number of Samples: | 76
Number of Exceedances: | 38
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Stream temperatures were measured by California Department of Fish and Game (CDFG) using data loggers (Stowaway, Tidbits and Hobo Temp Pros). Monitoring occurred from 1999 to 2007 depending on the monitoring station, identified by a river mile. The 7DADM was recorded weekly for each river mile. The maximum 7DADM value was calculated for each year. Based on the data provided, 38 out of 76 maximum 7DADM values exceeded the <18oC criteria from 1999 to 2007.
Data Reference: | Cover letter, data and information regarding elevated water temperatures in the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
| Access and DSS database files of water temperature data, one each for the San Joaquin, Merced, Stanislaus, and Tuolumne rivers
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 Water Board that such alteration in temperature does not adversely affect beneficial uses. In determining compliance with the water quality objectives for temperature, appropriate averaging periods may be applied provided that beneficial uses will be fully protected. (Central Valley Regional Board Basin Plan, Pg. III-8.00, Water Quality Objectives)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The guideline used was the 2003 US EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards (USEPA, 2003). The document includes recommended temperature criteria for salmon and trout based on different life stages. The recommended temperature for salmon and trout adult migration is <18oC for a 7DADM. The adult migration life stage occurs from river mile 0 (confluence with the San Joaquin River) to river mile 58 (Goodwin Dam). This life stage occurs during Julian weeks 36 through 43, which is approximately September 1st through October 31st.
Guideline Reference: | EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. U.S. Environmental Protection Agency Region 10 Office of Water, Seattle, WA.
Spatial Representation: | The adult migration life stage occurs from river mile 0 (confluence with the San Joaquin River) to river mile 58 (Goodwin Dam). Stream temperatures were monitored at the following stream locations during the adult migration life stage: River Miles 0 (confluence with the San Joaquin River), 15 (Hwy 99), 16 (Stouffer Park), 19 (Spring Creek Country Club), 29 (McHenry Access), 31 (Army Corp of Engineers property), 33 (Jacob Meyers Park), 34 (Army Corp of Engineers property), 38 (Gambini property), 40 (Oakdale Recreation Area), 46 (Orange Blossom Bridge), 54 (Sonora Road Bridge), and 58 (Goodwin Dam).
Temporal Representation: | The adult migration life stage occurs during Julian weeks 36 through 43, which is approximately September 1st through October 31st. Data was collected during this life stage on a continuous basis (hourly intervals) from 1991 through 2007, depending on the station and year monitored. Refer to the CDFG 2007 report (Gordus, 2007) for specific years for each location.
Environmental Conditions: |
QAPP Information: | Data is supported by a Quality Assurance Project Plan (QAPP) pursuant to the requirements of 40 CFR 31.45 and are acceptable for use in developing the section 303(d) list.
QAPP Information Reference(s):

DECISION ID | 7505
Pollutant: | Group A Pesticides
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (TMDL required list)(2006)
Revision Status | Original
Sources: | Agriculture
Expected TMDL Completion Date: | 2011
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | 303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.
RWQCB Board Decision / Staff Recommendation: | No new data were assessed for 2008. The decision has not changed.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7505

LOE ID: | 4563
Pollutant: | Group A Pesticides
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Not Recorded
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: | Placeholder reference pre-2006 303(d)
Water Quality Objective/Criterion: | Unspecified
Objective/Criterion Reference: | Placeholder reference pre-2006 303(d)
Evaluation Guideline: | Unspecified
Guideline Reference: | Placeholder reference pre-2006 303(d)
Spatial Representation: | Unspecified
Temporal Representation: | Unspecified
Environmental Conditions: | Unspecified
QAPP Information: | Unspecified
QAPP Information Reference(s):

DECISION ID | 7506
Pollutant: | Mercury
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (TMDL required list)(2006)
Revision Status | Original
Sources: | Resource Extraction
Expected TMDL Completion Date: | 2020
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | 303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.
RWQCB Board Decision / Staff Recommendation: | No new data were assessed for 2008. The Regional Board will update this decision when new data and information become available and are assessed.
SWRCB Board Decision / Staff Recommendation: | N/A
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 7506

LOE ID: | 4564
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Not Recorded
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: | Placeholder reference pre-2006 303(d)
Water Quality Objective/Criterion: | Unspecified
Objective/Criterion Reference: | Placeholder reference pre-2006 303(d)
Evaluation Guideline: | Unspecified
Guideline Reference: | Placeholder reference pre-2006 303(d)
Spatial Representation: | Unspecified
Temporal Representation: | Unspecified
Environmental Conditions: | Unspecified
QAPP Information: | Unspecified
QAPP Information Reference(s):