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

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Del Puerto Creek
Water Body ID: | CAR5411000020011212111305
Water Body Type: | River & Stream

DECISION ID | 6165
Pollutant: | Chlorpyrifos
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 removal on the section 303(d) list under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. 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. There is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1 of the Policy. 3. Eleven of 99 available 4-day average concentrations exceeded the 4-day average maximum concentration criterion and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. In addition, 13 of 124 available 1-hour average concentrations exceeded the 1-day average concentration criterion and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. The San Joaquin River Organophosphorous Pesticide TMDL has been approved by the Central Valley Water Board in 2005 and approved by USEPA on 12/20/2006. 5. Pursuant to section 4.11 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 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 6165

LOE ID: | 21948
Pollutant: | Chlorpyrifos
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: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 4-day average concentrations and 19 1-hour average concentrations.1 of 19 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 µg/L. 1 of 19 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Criteria - 0.015 µg/L 4-day average and 0.025 µg/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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 Del Puerto Creek at Vineyard Road.
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: | 21947
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 3
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 3 4-day average concentrations and 19 1-hour average concentrations.2 of 3 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 µg/L. 4 of 19 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Criteria - 0.015 µg/L 4-day average and 0.025 µg/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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 Del Puerto Creek at Vineyard Road.
Temporal Representation: | Samples were collected at variable intervals (hourly or daily) from February 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: | 4307
Pollutant: | Chlorpyrifos
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 Asses 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: | 21941
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 32
Number of Exceedances: | 4
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 32 water samples were collected from Del Puerto Creek from July 2004 through August 2006, representing 32 4-day average concentrations and 32 1-hour average concentrations.4 of 32 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 µg/L. 4 of 32 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 µg/L.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Criteria - 0.015 µg/L 4-day average and 0.025 µg/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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 Del Puerto Creek at Highway 33 and near Rox Road.
Temporal Representation: | Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21942
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 45
Number of Exceedances: | 4
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 54 Water samples were collected from Del Puerto Creek from January 2000 through February 2005, representing 45 4-day average concentrations and 54 1-hour average concentrations.4 of 45 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.015 µg/L. 4 of 54 available 1-hour average concentrations exceeded the maximum 1-hour chlorpyrifos concentration of 0.025 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Criteria - 0.015 µg/L 4-day average and 0.025 µg/L 1-hour average (Siepmann and Finlayson, 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005).
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 Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

DECISION ID | 6167
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 removal on the section 303(d) list under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. 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. There is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1 of the Policy. 3. Seven of 105 available 4-day average concentrations exceeded the 4-day average maximum concentration criterion and this exceeds the 4-day average maximum concentration criterion more than once every three years. In addition, 7 of 127 available 1-hour average concentrations exceeded the 1-hour average concentration criterion and this exceeds the 1-hour average concentration criterion more than once every three years. 4. The San Joaquin River Organophosphorous Pesticide TMDL has been approved by the Central Valley Water Board in 2005 and approved by USEPA on 12/20/2006. 5. Pursuant to section 4.11 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 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 6167

LOE ID: | 4308
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 Asses 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: | 21975
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 Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 4-day average concentrations and 19 1-hour average concentrations.0 of 19 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 µg/L. 0 of 19 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 µg/L 1-hour average and 0.100 µg/L 4-day average concentration 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 Del Puerto Creek at Vineyard Avenue.
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: | 21976
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 Asses Water Quality: | 2 water samples were collected from Del Puerto Creek from January through March 2006, representing 2 4-day average concentrations and 2 1-hour average concentrations.0 of 2 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 µg/L. 0 of 2 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Fish and Game Hazard Assessment Criteria - 0.160 µg/L 1-hour average and 0.100 µg/L 4-day average concentration 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 Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Two samples were collected. One sample was collected in February and one in March.
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: | 21977
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 32
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 32 water samples were collected from Del Puerto Creek from July 2004 through August 2006, representing 32 4-day average concentrations and 32 1-hour average concentrations.2 of 32 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 µg/L. 2 of 32 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 µg/L.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Fish and Game Hazard Assessment Criteria - 0.160 µg/L 1-hour average and 0.100 µg/L 4-day average concentration 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 Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: | Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21978
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 48
Number of Exceedances: | 5
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 54 Water samples were collected from Del Puerto Creek from January 2000 through February 2005, representing 48 4-day average concentrations and 54 1-hour average concentrations.5 of 48 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 µg/L. 5 of 54 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Fish and Game Hazard Assessment Criteria - 0.160 µg/L 1-hour average and 0.100 µg/L 4-day average concentration 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 Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
LOE ID: | 21970
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 3
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 3 4-day average concentrations and 19 1-hour average concentrations.0 of 3 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 0.1 µg/L. 0 of 19 available 1-hour average concentrations exceeded the maximum 1-hour concentration of 0.16 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 µg/L 1-hour average and 0.100 µg/L 4-day average concentration 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 Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (hourly or daily) from February 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

DECISION ID | 14730
Pollutant: | Azinphos-methyl (Guthion)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
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. Four lines of evidence are available in the administrative record to assess this pollutant. One 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. One of 126 samples exceeded the water quality criterion 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 14730

LOE ID: | 21956
Pollutant: | Azinphos-methyl (Guthion)
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 Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 19 concentrations.0 of 19 available concentrations exceeded the criterion of 0.01 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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
| Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Evaluation Guideline: | Water quality criterion is 0.01 µg/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: | Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Spatial Representation: | Samples were collected from Del Puerto Creek at Vinyard Road.
Temporal Representation: | Samples were collected daily during two storms in February and 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: | 21957
Pollutant: | Azinphos-methyl (Guthion)
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 Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 concentrations.0 of 19 available concentrations exceeded criterion of 0.01 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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
| Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Evaluation Guideline: | Water quality criterion is 0.01 µg/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: | Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road.
Temporal Representation: | Samples were collected at variable intervals (weekly and biweekly) from March to 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: | 21959
Pollutant: | Azinphos-methyl (Guthion)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 54
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 54 water samples were collected from Del Puerto Creek from January 2000 through February 2005, representing 54 concentrations. 1 of 54 concentrations exceeded criterion of 0.01 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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
| Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Evaluation Guideline: | Water quality criterion is 0.01 µg/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: | Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (e.g. daily, weekly) 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: | 21958
Pollutant: | Azinphos-methyl (Guthion)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 32
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 32 water samples were collected from Del Puerto Creek from April 2005 through August 2006, representing 32 concentrations.0 of 32 available concentrations exceeded the water quality criterion (0.01 µg/L).
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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
| Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Evaluation Guideline: | Water quality criterion is 0.01 µg/L for freshwater and marine aquatic life in the U.S. Environmental Protection Agency, Quality Criteria for Water [The Red Book] (USEPA, 1976). http://www.epa.gov/waterscience/criteria/redbook.pdf
Guideline Reference: | Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Spatial Representation: | Samples were collected from Del Puerto Creek at highway 33 and near Cox Road.
Temporal Representation: | Samples were collected at daily and biweekly intervals from April 2004 through August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 7818
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 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 8 available concentrations exceeded the California Toxics Rule for Warm Freshwater Habitat and this does not exceed the allowable frequency using Table 3.1 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 7818

LOE ID: | 6235
Pollutant: | Cadmium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 8
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Zero of the 8 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Cadmium.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Westside Basin
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) 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)) (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
| Compilation of Water Quality Goals - 2007 for toxicity data
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | The samples were collected from Sep 26 2001 to Oct 30 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 | 14731
Pollutant: | Cis-permethrin
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 lines of evidence are available in the administrative record to assess this pollutant. One 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. One of 35 samples exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14731

LOE ID: | 21749
Pollutant: | Cis-permethrin
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 35
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Thirty-five water samples were collected from Del Puerto Creek from October 1992 through August 2001 representing 35 concentrations. One sample had a concentrations less than the quantitation limit, and the quantitation limit that is greater than the Evaluation Guideline and, therefore, this sample was not used in this assessment, in accordance with section 6.1.5.5 of the Listing Policy.
Data Reference: | National Water Quality Assessment database, San Joaquin and Tulare Basins data
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The 24-hour LC50 for cis-permethrin, for the most sensitive species (Tanytarsus sp., a midge) is 0.033 ug/L. Therefore, the one-tenth LC50 value for the cis-permethrin Evaluation Guideline is 0.0033 ug/L.
Guideline 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
| ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road, near Patterson.
Temporal Representation: | Samples were collected at variable intervals (biweekly, weekly, monthly) from October 1992 through August 2001.
Environmental Conditions: |
QAPP Information: | Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):

DECISION ID | 14735
Pollutant: | DDE
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 one line(s) of evidence are necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. Data is not usable because it has high Reporting Limits according to section 6.5.1.1 of the Listing Policy. 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. Data is not usable because it has high Reporting Limits according to section 6.5.1.1 of the Listing Policy. A minimum of 2 samples is needed for application of table 3.1. 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 14735

LOE ID: | 21936
Pollutant: | DDE
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Thirty four samples were collected from Del Puerto Creek and analyzed for DDE, a metabolite of DDT, between January 2000 and August 2001. Data is not usable because it has high Reporting Limits and can not be determined if the 34 samples exceeded the California Toxic Rule/USEPA (CTR/USEPA) criteria DDE limit of 0.00059 µg/L based on a human health 10-6 carcinogenic risk for consumption of water and aquatic organisms.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | - Sacramento/San Joaquin River Basin Plan (CVRWQCB, 2007a).Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer.- California Toxics Rule Criteria (USEPA, 2000)Inland Surface Waters based on drinking water and aquatic organism consumption. The criteria are based on human health protection for carcinogenicity at 1-in-a-million risk level (30-day average) for DDE of less than 0.00059 µg/L.
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
| 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 from Del Puerto Creek at Vineyard Ave. (tributary to San Joaquin River), Stanislaus County.
Temporal Representation: | Samples were collected at weekly intervals within specific months (January and February in 2000; April ¿ August in 2001).
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 7819
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 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 14 available concentrations exceeded the California Toxics Rule for Warm Freshwater Habitat and this does not exceed the allowable frequency using Table 3.1 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 7819

LOE ID: | 6237
Pollutant: | Lead
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Zero of the 14 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Lead.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Westside Basin
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) Lead levels should not exceed the calculated 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)) (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
| Compilation of Water Quality Goals - 2007 for toxicity data
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | The samples were collected from Nov 29 2000 to Oct 30 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 | 14732
Pollutant: | Methyl Parathion
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
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. Two lines of evidence are available in the administrative record to assess this pollutant. Three 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. Three of 66 samples exceeded the interim water quality criterion 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 14732

LOE ID: | 21955
Pollutant: | Methyl Parathion
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 12 water samples were collected from Del Puerto Creek from July 2004 through August 2006, representing 12 concentrations.3 of 12 available concentrations exceeded the interim water quality criterion 0.08 µg/L. 24 water samples had method detection limits (0.1 µg/L) higher than the Criterion (0.08 µg/L). So the 24 samples were not included in this analysis.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Criteria - Interim water quality criterion is 0.08 µg/L (Menconi and Harrington, 1992).
Guideline Reference: | Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
Spatial Representation: | Samples were collected from Del Puerto Creek at two locations: Highway 33 and near Rox Road.
Temporal Representation: | Samples were collected monthly from July 2004 through August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21954
Pollutant: | Methyl Parathion
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 54
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 54 Water sample was collected from Del Puerto Creek from January 2000 through February 2005, representing 54 concentrations.0 of 54 available concentrations exceeded the interim water quality criterion 0.08 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Criteria - Interim water quality criterion is 0.08 µg/L (Menconi and Harrington, 1992).
Guideline Reference: | Hazard Assessment of the Insecticide Methyl Parathion to Aquatic Organisms in the Sacramento River System. California Department of Fish and Game. Environmental Services Division. Administrative Report 92-1
Spatial Representation: | Samples were collected from Del Puerto Creek at location (lat. 37.5217 and Long. -121.148)
Temporal Representation: | Samples were collected at variable intervals (e.g. daily, weekly) from January 2000 through February 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

DECISION ID | 7821
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 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 14 available concentrations exceeded the California Toxics Rule for Warm Freshwater Habitat and this does not exceed the allowable frequency using Table 3.1 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 7821

LOE ID: | 6242
Pollutant: | Nickel
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Zero of the 14 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Nickel.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Westside Basin
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) Nickel levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration (1-hour Average, dissolved)=(EXP(0.846*LN(hardness)+2.255))*(0.998)(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
| Compilation of Water Quality Goals - 2007 for toxicity data
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | The samples were collected from Nov 29 2000 to Oct 30 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 | 7822
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 11 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 11 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 7822

LOE ID: | 6243
Pollutant: | Nitrate as Nitrate (NO3)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 11
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Zero of the 11 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation guideline for Nitrate-N.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Westside Basin
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
Spatial Representation: | Samples were collected at Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | The samples were collected from Oct 24 2000 to Oct 24 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 | 14733
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 placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Two 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. Two of 223 samples fell below the minimum criterion water quality objective listed in the Sacramento/San Joaquin River Basin Plan and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14733

LOE ID: | 21982
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 162
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | One-hundred-sixty-two samples were taken from Del Puerto Creek between 2001 and 2005. One of the one-hundred- sixty-two samples fall below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/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 from Del Puerto Creek at Vineyard, Deer Creek, Rogers, Del Puerto Mile 3.9, Del Puerto Mile 13.6 and Highway 33 in Stanislaus County.
Temporal Representation: | Samples were collected between June 2001 and November 2005. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Data quality: Good. 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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21981
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 61
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Sixty-one samples were taken from Del Puerto Creek between 2004 and 2006. One of the sixty-one samples falls below the Water Quality Objective for minimum dissolved oxygen content in surface water.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | From the Sacramento/San Joaquin River Basin Plan the (WARM) Warm Freshwater Habitat criterion is a Minimum Dissolved Oxygen content of 5mg/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 from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: | Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 14734
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 placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. One 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. One of 7 samples exceeded the selenium objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14734

LOE ID: | 21952
Pollutant: | Selenium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
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 Asses Water Quality: | The Westside San Joaquin River Water Quality Coalition collected six samples from 1 July 2006 to 31 October 2006. One out of the six samples collected exceeded the evaluation objective.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | CTR criterion of 5 ug/L, total recoverable Se, for the protection of freshwater aquatic life (4-day average concentration to protect from extended period of exposure).
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
| 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 two sites: Del Puerto Creek at Highway 33 and Del Puerto Creek Near Cox Road.
Temporal Representation: | Monthly sampling occurred during the irrigation season.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21953
Pollutant: | Selenium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected one sample on 30 October 2002.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | CTR criterion of 5 ug/L, total recoverable Se, for the protection of freshwater aquatic life (4-day average concentration to protect from extended period of exposure).
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
| 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: | A Sample was collected at Del Puerto Creek at Vineyard Rd
Temporal Representation: | This was a one-time sampling event.
Environmental Conditions: |
QAPP Information: | Data quality: Good. 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 | 14736
Pollutant: | Simazine
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. Four lines of evidence are available in the administrative record to assess this pollutant. One 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. One of 81 samples exceeded the drinking water standard (4 µg/L) 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 14736

LOE ID: | 21961
Pollutant: | Simazine
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 19
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from March to August 2003, representing 19 concentrations.0 of 19 available concentrations exceeded MCL (4 ug/L)
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449. The Maximum Contaminant Level (MCL) for simazine is 4 ug/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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road
Temporal Representation: | Samples were collected at variable intervals (weekly and biweekly) from March to 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: | 21960
Pollutant: | Simazine
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 19
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 19 water samples were collected from Del Puerto Creek from February to March 2003, representing 19 concentrations.0 of 19 available concentrations exceeded the MCL (4 µg/L).
Data Reference: | Zipped file of Central Valley Waterways Pesticide TMDL monitoring data spreadsheets and reports
Water Quality Objective/Criterion: | At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449. The Maximum Contaminant Level (MCL) for simazine is 4 µg/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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road.
Temporal Representation: | Samples were collected daily during two storms in February and 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: | 21938
Pollutant: | Simazine
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 9
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 9 water samples were collected from Del Puerto Creek from January through August 2006, representing 9 concentrations. 1 of 9 concentrations exceeded MCL (4 µg/L).
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449. The Maximum Contaminant Level (MCL) for simazine is 4 ug/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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference: | California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and Cox Road.
Temporal Representation: | One sample was collected in January 2005, and the other samples were collected monthly from January through August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21937
Pollutant: | Simazine
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 34
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 34 water samples were collected from Del Puerto Creek from January 2000 through August 2001, representing 34 concentrations.0 of 34 concentrations exceeded the MCLs for drinking water standard (4 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: | At a minimum, water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels (MCLs) specified in the following provisions of Title 22 of the California Code of Regulations, which are incorporated by reference into this plan: Tables 64431-A (Inorganic Chemicals) and 64431-B (Fluoride) of Section 64431, Table 64444-A (Organic Chemicals) of Section 64444, and Tables 64449-A (Secondary Maximum Contaminant Levels-Consumer Acceptance Limits) and 64449-B (Secondary Maximum Contaminant Levels-Ranges) of Section 64449. The Maximum Contaminant Level (MCL) for simazine is 4 ug/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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference: | California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (e.g. several samples per day, daily, and weekly) 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

DECISION ID | 14737
Pollutant: | Thiobencarb/Bolero
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. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 34 samples exceeded the concentration criterion 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 14737

LOE ID: | 21969
Pollutant: | Thiobencarb/Bolero
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 29
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 29 water samples were collected from Del Puerto Creek from January 2000 through August 2001, representing 29 concentrations. 0 of 29 concentrations exceeded Secondary MCL concentration of 1 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: | Secondary Maximum Contaminate Levels (MCLs) for drinking water standard adopted by the California Department of Public Health (CDPH) is 1 µg/L (CDPH, 2008).
Guideline Reference: | California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (e.g. daily, weekly) 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: | 21968
Pollutant: | Thiobencarb/Bolero
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 Asses Water Quality: | 5 water samples were collected from Del Puerto Creek from January 2005 through August 2006, representing 5 concentrations. 0 of 5 concentrations exceeded Secondary MCL concentration of 1 µg/L.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: | Secondary Maximum Contaminate Levels (MCLs) for drinking water standard adopted by the California Department of Public Health (CDPH) is 1 µg/L (CDPH, 2008).
Guideline Reference: | California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: | Samples were collected at variable intervals from January 2005 to August 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 14738
Pollutant: | Trifluralin
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. Four lines of evidence are available in the administrative record to assess this pollutant. Six 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. Six of 96 samples exceeded the narrative toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14738

LOE ID: | 21993
Pollutant: | Trifluralin
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 33
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 33 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from January 2000 through August 2001 representing 33 concentrations.2 of 33 concentrations exceeded the maximum concentration of 0.70 µg/L.
Data Reference: | 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
| Report and data files for pesticides in the Sacramento River, Winter 2005
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road Near Patterson, CA.
Temporal Representation: | Samples were collected during one storm in February 2000 and at variable intervals (biweekly, 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: | 21994
Pollutant: | Trifluralin
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 34
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 34 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from June 1994 through August 2001 representing 34 concentrations.2 of 34 concentrations exceeded the maximum concentration of 0.70 µg/L.
Data Reference: | National Water Quality Assessment database, San Joaquin and Tulare Basins data
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road Near Patterson, CA.
Temporal Representation: | Samples were collected during two storms in February 2000 and June 2001, and at variable intervals (biweekly, weekly, monthly) from June 1994 through August 2001.
Environmental Conditions: |
QAPP Information: | Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
LOE ID: | 21995
Pollutant: | Trifluralin
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 27
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | 27 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from July 2004 through June 2006 representing 27 concentrations.2 of 27 concentrations exceeded the maximum concentration of 0.70 µg/L.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek near Highway 33 and Cox Road Near Patterson, CA.
Temporal Representation: | Samples were collected at variable intervals (biweekly, weekly, monthly) from July 2004 through June 2006.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21967
Pollutant: | Trifluralin
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 Asses Water Quality: | 2 water samples were collected from Del Puerto Creek at Vineyard Road Near Patterson from February 2006 through March 2006 representing 2 concentrations.0 of 2 concentrations exceeded the maximum concentration of 0.70 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).Lowest Observed Effects Concentration for Pimephales promelas is 0.7 ug/L Ecotoxicity Study 1582-09-8 (USEPA, 2008)
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Road near Patterson, CA.
Temporal Representation: | Samples were collected at variable intervals (biweekly, weekly, monthly) from February 2006 through March 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

DECISION ID | 7839
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 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 14 available concentrations exceeded the California Toxics Rule for Warm Freshwater Habitat and this does not exceed the allowable frequency using Table 3.1 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 7839

LOE ID: | 6280
Pollutant: | Zinc
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 14
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Zero of the 14 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Zinc.
Data Reference: | San Joaquin River SWAMP Monitoring Data - Westside Basin
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) Dissolved Zinc levels should not exceed the calculated limit based on the formula: Criteria Maximum Concentration=EXP((0.8473*LN(hardness))+0.884)*(0.978) (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
| Compilation of Water Quality Goals - 2007 for toxicity data
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | The samples were collected from Nov 29 2000 to Oct 30 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 | 14739
Pollutant: | pH (low)
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 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Three 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. Three of 153 samples had pH values lower than the pH objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14739

LOE ID: | 21986
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 102
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 102 samples from November 2004 to November 2005. None of the 102 samples had a pH value lower than 6.5.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.
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: | Measurement of pH within the range of 6.5 and 8.5. A low pH has a value less than 6.5.
Guideline Reference:
Spatial Representation: | Samples were collected at five locations along Del Puerto Creek: Deer Creek, Rogers, Del Puerto Mile 3.9, Del Puerto Mile 13.6, and Highway 33.
Temporal Representation: | Sampling occurred from November 2004 to November 2005
Environmental Conditions: |
QAPP Information: | Data quality: Good. 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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21985
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 51
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | The Westside San Joaquin River Water Quality Coalition collected 51 samples from July 2004 to October 2006. Eight of the 51 samples did not meet the evaluation objective. Three samples had a pH lower than 6.5.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.
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: | Measurement of pH within the range of 6.5 and 8.5. A low pH has a value less than 6.5.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: | Sampling occurred from July 2004 to October 2006
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 13083
Pollutant: | Bifenthrin
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: | 2010
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. Two lines of evidence are available in the administrative record to assess this pollutant. Eight 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 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. Eight of 22 samples exceed the narrative toxicity objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13083

LOE ID: | 21939
Pollutant: | Bifenthrin
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 20
Number of Exceedances: | 8
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Water samples were collected from Del Puerto Creek from June 2003 through February 2005, representing 20 concentrations. 8 of 20 concentrations exceeded the maximum value (0.00093 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technicalinformation to evaluate compliance with the narrativeobjectives. ¿ the Board will consider one tenth of 96 hour LC50 for the most sensitive species tested as theupper limit (daily maximum) for the protection ofaquatic life (CRWQCB, 2006). The one tenth of 96 hour LC50 tested on the most sensitive species in freshwater is 0.00093 ug/L (ECOTOX, 2008).
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Samples were collected at variable intervals (e.g. weekly and monthly) from June 2003 through February 2005.
Environmental Conditions: |
QAPP Information: | 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: | 21940
Pollutant: | Bifenthrin
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 Asses Water Quality: | 2 water samples were collected from Del Puerto Creek from July 2006 through August 2006, representing 2 concentrations.0 of 2 concentrations exceeded the upper limit value (0.00093 µg/L).
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technicalinformation to evaluate compliance with the narrativeobjectives. ¿ the Board will consider one tenth of 96 hour LC50 for the most sensitive species tested as theupper limit (daily maximum) for the protection ofaquatic life (CRWQCB, 2006). The one tenth of 96 hour LC50 tested on the most sensitive species in freshwater is 0.00093 µg/L (ECOTOX, 2008).
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33.
Temporal Representation: | Samples were collected monthly between July 2006 and August 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 13082
Pollutant: | Copper
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 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One lines of evidence are available in the administrative record to assess this pollutant. Three 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 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. Three of 7 samples exceed the 4-day maximum criterion for total copper and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13082

LOE ID: | 21943
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 7
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Seven samples were taken from Del Puerto Creek in 2006. Three of the seven samples exceed guidelines for total copper. Three samples exceed the 4-day average concentration levels.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | California Toxics Rule Criteria (USEPA) - Freshwater Aquatic Life ProtectionContinuous Concentration (4-day Average) calculated based on the fallowing formula (e{.8545xLN[hardness]}-1.702) which incorporates hardnessU.S. Environmental Protection Agency, Federal Register, Volume 65, No. 97 (Thursday, 18 May 2000), pp. 31682-31719 [California Toxics Rule]; and Federal Register, Volume 66, No. 30 (Tuesday, 13 February 2001), pp. 9960-9962 [California Toxics Rule Correction] http://www.gpoaccess.gov/fr/browse.html.
Objective/Criterion Reference: | Water Quality 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
| 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 from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: | Samples were collected between July through October 2006. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 13085
Pollutant: | Dieldrin
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. One lines of evidence are available in the administrative record to assess this pollutant. Two 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 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. Two of 8 samples exceed the California Toxic Rule/USEPA (CTR/USEPA) criteria for Dieldrin of 0.00014 μg/L based on a human health 10-6 carcinogenic risk level for water and fish consumption and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13085

LOE ID: | 21949
Pollutant: | Dieldrin
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 8
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Thirty-three samples were collected from Del Puerto Creek and based on a 30-day average, the samples reduced to Eight samples. These were analyzed for Dieldrin between June 1994 and August 2001. Two of the Eight water samples exceeded the CTR criteria for Dieldrin of 0.00014 µg/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
| National Water Quality Assessment database, San Joaquin and Tulare Basins data
Water Quality Objective/Criterion: | - Sacramento/San Joaquin River Basin Plan for Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (CVRWQCB 2007).- California Toxics Rule Criteria (USEPA, 2000):Criteria based on Human Health Protection (30-day average) with a Dieldrin limit of less than 0.00014 µg/L for water and fish consumption.
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 from Del Puerto Creek at Vineyard Ave. (tributary to San Joaquin River).
Temporal Representation: | Samples were taken at weekly intervals within specific months (January and February in 2000; April ¿ August in 2001).
Environmental Conditions: |
QAPP Information: | 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
| National Field Manual for the Collection of Water-Quality Data, Techniques of Water-Resources Investigations, Book 9, Handbooks for Water-Resources Investigations

DECISION ID | 14335
Pollutant: | Dimethoate
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. Three lines of evidence are available in the administrative record to assess this pollutant. Fourteen 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 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. Fourteen of 54 water samples exceed the Evaluation Guideline of 0.2 ug/L (based on the one-tenth LC50 for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), and these exceed the narrative toxicity objective, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 14335

LOE ID: | 26080
Pollutant: | Dimethoate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 20
Number of Exceedances: | 6
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Twenty water samples were collected from Del Puerto Creek between June 2003 and February 2005, as reported in the DPR Surface Water Database. Six of the water samples exceeded the Evaluation Guideline of 0.2 µg/L.
Data Reference: | Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
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: | Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The one-tenth of 96-hour LC50 value for dimethoate for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 µg/L.
Guideline 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
| ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Spatial Representation: | Water samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Water samples were collected from Del Puerto Creek between June 2003 and February 2005 at intervals ranging from weekly to monthly.
Environmental Conditions: |
QAPP Information: | Data Quality: Good. Minimum requirements for the Surface Water Database are: Name of the sampling agency or organization Date that each sample was collected Date of each sample analysis County where samples were taken Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.) Name or description of water body sampled Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation Description of analytical QA/QC plan, or statement that no formal plan exists Additional optional requirements are included on DPRs webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm.
QAPP Information Reference(s):
LOE ID: | 26078
Pollutant: | Dimethoate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Asses Water Quality: | Two water samples were collected from Del Puerto Creek under the Pesticide TMDL program, on 28 February 2006 and on 1 March 2006. None of the samples exceeded the Evaluation Guideline of 0.2 ug/L. 0 of 2 available concentrations exceeded the criterion (0.2 µg/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: | Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The one-tenth of 96-hour LC50 value for dimethoate for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 µg/L.
Guideline 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
| ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Spatial Representation: | Water samples were collected from Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Water samples were collected from Del Puerto Creek on 28 February 2006 and on 1 March 2006.
Environmental Conditions: |
QAPP Information: | Data Quality: Good. All sampling, analysis and QA/QC protocols are described in a QAPP prepared for the Pesticide TMDL program sampling.
QAPP Information Reference(s):
LOE ID: | 26079
Pollutant: | Dimethoate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 32
Number of Exceedances: | 8
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Thirty-two water samples were collected from Del Puerto Creek under the Irrigated Lands Regulatory Program, between June 2004 and August 2006. Eight of the samples exceeded the Evaluation Guideline of 0.2 ug/L. One sample had a dimethoate concentration less than quantitation limit (0.5 ug/L), which is greater than the Evaluation Guideline. 0 of 2 available concentrations exceeded the criterion (0.2 µg/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: | Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives. The one-tenth of 96-hour LC50 value for dimethoate for the most sensitive species in freshwater (Cyclops strenuus, a copepod crustacean), is 0.2 µg/L.
Guideline 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
| ECOTOX database, aquatic data. U. S. Environmental Protection Agency
Spatial Representation: | Water samples were collected from Del Puerto Creek at Highway 33 and at Cox Road.
Temporal Representation: | Water samples were collected from Del Puerto Creek monthly between June 2004 and August 2006.
Environmental Conditions: |
QAPP Information: | Data Quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826 ) requirements.
QAPP Information Reference(s):

DECISION ID | 13081
Pollutant: | Diuron
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. Three lines of evidence are available in the administrative record to assess this pollutant. Two 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 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. Two of 7 samples exceed the narrative toxicity objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13081

LOE ID: | 21944
Pollutant: | Diuron
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: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Two water samples were collected at Del Puerto Creek in 2006.1 of 2 concentrations exceeded the maximum concentration of 1.3 µg/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 (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species is 1.3 µg/L (ECOTOX, 2008).
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
Spatial Representation: | Del Puerto Creek at Vineyard Avenue
Temporal Representation: | Samples were collected daily during a storm event on February 28 and March 1, 2006.
Environmental Conditions: |
QAPP Information: | 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: | 21980
Pollutant: | Diuron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Six water samples were collected at Del Puerto Creek on March 15, 2003. Because all samples were collected within a 6 hour period of time, the mean was taken of the samples and compared to the maximum concentration (EC50) for diuron.1 of 1 concentration exceeded the maximum concentration of 1.3 µg/L.
Data Reference: | The Occurrence and Concentration of Esfenvalerate and Permethrin in Water and Sediment in the Sacramento and San Joaquin Watersheds
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species is 1.3 µg/L (ECOTOX, 2008).
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
Spatial Representation: | Del Puerto Creek at Vineyard Road.
Temporal Representation: | Samples were collected hourly for 6 hours on March 15, 2003.
Environmental Conditions: |
QAPP Information: | Sampling was conducted using DPRs Standard Operating Procedures (SOPs) for pesticides (Bennett, 1997). Sample quality control was conducted according to Segawa, 1995.
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
LOE ID: | 21979
Pollutant: | Diuron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 4
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Four water samples were collected at Del Puerto Creek in 2006.0 of 4 concentrations exceeded the maximum concentration of 1.3 µg/L.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses (CVRWQCB, 2007).All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007).
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 Board will use the best available technical information to evaluate compliance with the narrative objectives. ¿Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.¿ (CRWQCB, 2006).The 96 hour EC50 for the most sensitive species is 1.3 µg/L (ECOTOX, 2008).
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
Spatial Representation: | Del Puerto Creek at Highway 33 and Del Puerto Creek near Cox Road.
Temporal Representation: | Samples were collected on 7/11/2006 and 08/08/2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 7577
Pollutant: | Escherichia coli (E. Coli)
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. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Ninety-two 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 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. Ninety-two of 196 samples exceed the E. Coli objective and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 7577

LOE ID: | 5010
Pollutant: | Escherichia coli (E. Coli)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 144
Number of Exceedances: | 60
Data and Information Type: | Water column surveys (e.g. fecal coliform)
Data Used to Asses Water Quality: | The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 144 samples from November 2004 to November 2005. Sixty out of 144 samples exceeded the evaluation objective.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: | 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 USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: | Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
Spatial Representation: | Samples were collected at six locations: Del Puerto Creek at Deer Creek Campground, Del Puerto Creek at Del Puerto Canyon Road Mile 13.6, Del Puerto Creek at Del Puerto Canyon Road Mile 3.9, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33 and Del Puerto Creek at Vineyard Avenue.
Temporal Representation: | Sampling occurred from July 2002 to November 2005.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with the State Water Resources Control Boards Quality Assurance Program Plan for the State of Californias Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 5007
Pollutant: | Escherichia coli (E. Coli)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 52
Number of Exceedances: | 32
Data and Information Type: | Water column surveys (e.g. fecal coliform)
Data Used to Asses Water Quality: | The Westside San Joaquin River Water Quality Coalition collected 52 samples from July 2004 to October 2006. Thirty-two out of the 52 samples collected exceeded the evaluation objective.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. The objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances.
Objective/Criterion Reference: | 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 USEPA E. Coli objective of 235/100 mL in any single sample (USEPA 1986).
Guideline Reference: | Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
Spatial Representation: | Samples were collected at two locations: Del Puerto Creek at Highway 33 and Del Puerto Creek near Cox Road.
Temporal Representation: | Monthly sampling occurred July 2004 to October 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 13077
Pollutant: | Salinity
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. Under section 3.2 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Fifty-three 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 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. Fifty-three of 141 samples exceed the water quality objectives for electrical conductivity and total dissolved solids (collectively salinity) and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13077

LOE ID: | 21989
Pollutant: | Salinity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 30
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Thirty samples were taken from Del Puerto Creek between 2004 and 2006. Three of the thirty samples exceed the California Secondary MCL for EC in surface water.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | The water quality objective used was the California Secondary MCL recommended level of 900 uS/cm. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL¿s) protective of MUN (CVRWQCB, 2007a).The secondary MCL¿s for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The ¿recommended¿ concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: | Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21992
Pollutant: | Salinity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 10
Number of Exceedances: | 6
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Ten samples were taken from Del Puerto Creek between 2000 and 2002. Six of the 10 samples exceed the California Secondary MCL for TDS in surface water.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | The water quality objective used was the California Secondary MCL recommended level of 500 mg/L. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL¿s) protective of MUN (CVRWQCB, 2007a).The secondary MCL¿s for TDS provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The ¿recommended¿ concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard, Deer Creek, Highway 33, Del Puerto 3.9 and Del Puerto 13.6 in Stanislaus County.
Temporal Representation: | Samples were collected between October 2000 and October 2002. Samples were collected at monthly intervals.
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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21990
Pollutant: | Salinity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 73
Number of Exceedances: | 37
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Seventy-three samples were taken from Del Puerto Creek between 2000 and 2005. Thirty-seven of the seventy-three samples exceed the California Secondary MCL for EC in surface water.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | The water quality objective used was the California Secondary MCL recommended level of 900 uS/cm. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL¿s) protective of MUN (CVRWQCB, 2007a).The secondary MCL¿s for electrical conductivity provide a range of values including a recommended level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The ¿recommended¿ concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Vineyard, Deer Creek, Highway 33, Del Puerto 3.9 and Del Puerto 13.6 in Stanislaus County.
Temporal Representation: | Samples were collected between October 2000 and November 2005. Samples were collected at monthly intervals.
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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21991
Pollutant: | Salinity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 28
Number of Exceedances: | 7
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Twenty-eight samples were taken from Del Puerto Creek between 2004 and 2006. Seven of the twenty-eight samples exceed the California Secondary MCL for TDS in surface water.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | The water quality objective used was the California Secondary MCL recommended level of 500 mg/L. The Basin Plan includes chemical constituent water quality objectives that include (by reference) secondary maximum contaminant levels (MCL¿s) protective of MUN (CVRWQCB, 2007a).The secondary MCL¿s for TDS provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The ¿recommended¿ concentration was used as it is intended to be protective of all drinking water uses. Though individual listing evaluations did not look at the water supply source serving the given geographic area, there are certain areas that receive supply waters (such as the Delta Mendota Canal) that at times may be elevated above the recommended level of the secondary MCL. Where future information is made available to document this to be the case, these water bodies may be re-evaluated in future listing cycles.
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
| California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring. http://www.cdph.ca.gov/certlic/drinkingwater/Pages/Lawbook.aspx
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road in Stanislaus County.
Temporal Representation: | Samples were collected between July 2004 and October 2006. Samples were collected at monthly intervals.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 13079
Pollutant: | Sediment Toxicity
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. Two lines of evidence are available in the administrative record to assess this pollutant. Ten 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 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 12 samples exceed the narrative toxicity objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13079

LOE ID: | 21972
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Sediment
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 3
Number of Exceedances: | 2
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | Two of the 3 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(1)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:11 September 2006(56)
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
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.¿ (CVRWQCB, 2007)
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 t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: | Samples were collected from September 2004 to September 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21973
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Sediment
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 9
Number of Exceedances: | 8
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | Eight of the 9 samples tested with Hyalella azteca were toxic and violated the narrative toxicity objective. One sample collected at Rogers exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:28 October 2002(46)6 samples collected at Vineyard exhibited a statistically significant decrease in survival compared to the control. The sample dates and percent of control (in parentheses) are as follows:9 October 2001(0)29 May 2002(65)28 October 2002(6)28 October 2002(50)9 April 2003(40)15 June 2005(40)One sample collected near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 October 2005(0)
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
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.¿ (CVRWQCB, 2007)
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 t-test with 10-day Hyalella azteca sediment toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33, Rogers, Vineyard and near Cox Road.
Temporal Representation: | Samples were collected from October 2001 to October 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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

DECISION ID | 13078
Pollutant: | Unknown Toxicity
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 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Twenty-eight 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 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. Twenty-four of 68 samples tested with selenastrum exceed the narrative toxicity objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13078

LOE ID: | 21974
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 31
Number of Exceedances: | 1
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | 1 of 31 samples tested with Selenastrum capricornutum was toxic and violated the narrative toxicity objective. One sample collected at Highway 33 exhibited a statistically significant decrease in growth compared to the control. The sample date and percent of control (in parentheses) are as follows:29 December 2004 (3)
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
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.¿ (CVRWQCB, 2007)
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 t-test with 4-day chronic-style toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: | Samples were collected from July 2004 to August 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21945
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 32
Number of Exceedances: | 2
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | 2 of the 32 samples tested with Ceriodaphnia dubia were toxic and violated the narrative toxicity objective. One sample collected at Del Puerto Creek at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:29 December 2004 (0)One sample collected at Del Puerto Creek near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:10 August 2004 (0)
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
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.¿ (CVRWQCB, 2007)
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 t-test with 4-day acute-style toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from two locations: Del Puerto Creek at Highway 33 and Del Puerto Creek near Cox Road.
Temporal Representation: | Samples were collected from July 2004 to August 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 22033
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 37
Number of Exceedances: | 23
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | 23 of 37 samples tested with Selenastrum capricornutum were toxic and violated the narrative toxicity objective. Nine samples collected at Deer Creek Campground exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:16 November 2004 (81)21 December 2004 (77)17 May 2005 (75)21 June 2005 (87)19 July 2005 (83)16 August 2005 (78)20 September 2005 (77)18 October 2005 (66)15 November 2005 (85)\Ten samples collected at Del Puerto Mile 3.9 exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:15 February 2005 (81)23 March 2005 (87)19 April 2005 (71)17 May 2005 (64)21 June 2005 (70)19 July 2005 (66)16 August 2005 (71)20 September 2005 (71)18 October 2005 (62)15 November 2005 (75)Four samples collected at Highway 33 exhibited a statistically significant decrease in growth compared to the control. The sample dates and percent of control (in parentheses) are as follows:21 December 2004 (4)15 February 2005 (22)23 March 2005 (75)21 June 2005 (57)
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
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.¿ (CVRWQCB, 2007)
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 t-test with 4-day chronic-style toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Deer Creek Campground, Del Puerto Mile 3.9 and Highway 33.
Temporal Representation: | Samples were collected from November 2004 to November 2005 at monthly intervals.
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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21987
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 32
Number of Exceedances: | 1
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | One of the 32 samples tested with Pimephales promelas was toxic and violated the narrative toxicity objective. One sample collected at Del Puerto Creek near Cox Road exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:14 June 2005 (90)
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
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.¿ (CVRWQCB, 2007)
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 t-test with 4-day acute-style toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from two locations: Del Puerto Creek at Highway 33 and Del Puerto Creek near Cox Road.
Temporal Representation: | Samples were collected from July 2004 to August 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):
LOE ID: | 21946
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 13
Number of Exceedances: | 1
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | One of the 13 samples tested with Ceriodaphnia dubia was toxic and violated the narrative toxicity objective. One sample collected at Del Puerto Creek at Highway 33 exhibited a statistically significant decrease in survival compared to the control. The sample date and percent of control (in parentheses) are as follows:21 December 2004 (0)
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
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.¿ (CVRWQCB, 2007)
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 Fisher¿s Exact analysis with 4-day acute-style toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33.
Temporal Representation: | Samples were collected from November 2004 to November 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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21988
Pollutant: | Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 13
Number of Exceedances: | 0
Data and Information Type: | TOXICITY TESTING
Data Used to Asses Water Quality: | None of the 13 samples tested with Pimephales promelas were toxic and violated the narrative toxicity objective.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
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. (CVRWQCB, 2007)
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 Fisher's Exact analysis with 4-day acute-style toxicity tests.
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33
Temporal Representation: | Samples were collected from November 2004 to November 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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

DECISION ID | 13080
Pollutant: | pH (high)
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. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Thirty-three 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 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. Thirty-three of 153 samples had pH values higher than the pH objective and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
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 13080

LOE ID: | 21984
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 102
Number of Exceedances: | 25
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | The Central Valley Regional Water Quality Control Board Surface Water Ambient Monitoring Program collected 102 samples from November 2004 to November 2005. Twenty-five out of the 102 samples had a pH value over 8.5 and thus did not meet the evaluation objective.
Data Reference: | Monitoring Data from the Surface Water Ambient Monitoring Program (SWAMP), San Joaquin River Basin - 2007 Data Review
Water Quality Objective/Criterion: | The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.
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: | Measurement of pH within the range of 6.5 and 8.5. A high pH value is greater than 8.5
Guideline Reference:
Spatial Representation: | Samples were collected at five locations along Del Puerto Creek:Deer CreekRogersDel Puerto Mile 3.9Del Puerto Mile 13.6Highway 33
Temporal Representation: | Sampling occurred from November 2004 to November 2005
Environmental Conditions: |
QAPP Information: | Data quality: Good. 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): | Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
LOE ID: | 21983
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Aquatic Life Use: | Warm Freshwater Habitat
Number of Samples: | 51
Number of Exceedances: | 8
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | The Westside San Joaquin River Water Quality Coalition collected 51 samples from July 2004 to October 2006. Eight of the 51 samples did not meet the evaluation objective. Five samples had a pH higher than 8.5.
Data Reference: | Revised Draft of the 2007 Review of the Monitoring Data for the Irrigated Lands Regulatory Conditional Waiver Program
| Monitoring and Reporting Program, Order Nos. R5-2003-0826, R5-2005-0833, and R5-2008-0005 for Coalition Groups Under Resolution No. R5-2003-0105, Conditional Waiver of Waste Discharge Requirements for Discharges From Irrigated Lands Within the Central Valley Region
Water Quality Objective/Criterion: | The pH of water shall not be depressed below 6.5,raised above 8.5, or changed at any time more than 0.5 units from normal ambient pH.
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: | Measurement of pH within the range of 6.5 and 8.5. A high pH value is greater than 8.5
Guideline Reference:
Spatial Representation: | Samples were collected from Del Puerto Creek at Highway 33 and near Cox Road.
Temporal Representation: | Sampling occurred from July 2004 to October 2006
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2003-0826) requirements (CVRWQCB, 2003)
QAPP Information Reference(s):

DECISION ID | 5357
Pollutant: | Pyrethroids
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: | 2010
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 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. Based on section 3.6 the site has significant sediment toxicity and the pollutant is likely to cause or contribute to the toxic effect. A TIE is available that indicates pyrethroid pesticides are a likely cause of toxicity. 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. Five of 7 samples exhibit sediment toxicity and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. A TIE has been completed and the likely cause of toxicity is pyrethroid pesticides. 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: | This is a decision made by the State Water Resources Control Board and approved by the USEPA in 2006 . No new data were assessed by the Regional Board for 2008. The decision has not changed.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 5357

LOE ID: | 2782
Pollutant: | Sediment Toxicity
LOE Subgroup: | Toxicity
Matrix: | Sediment
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 7
Number of Exceedances: | 5
Data and Information Type: | Toxicity testing of sediments
Data Used to Asses Water Quality: | Five out of seven samples displayed statistically significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%. All samples were tested using the 10-day Hyalella azteca test. Samples were collected at: -Del Puerto Creek at Vineyard, on 10/9/2001, 5/29/2002 (CVRWQCB, 2002), 10/28/2002, 9/11/2002 (CVRWQCB, 2002), 4/11/2003 -Del Puerto Creek at Hwy 33 on 10/28/2002 -Del Puerto Creek 100 feet upstream of Vineyard Lane bridge on 10/28/2002 -note: samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and have not been included in the counts (SWAMP, 2004).
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998).
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected at three sites. Toxicity in the survival endpoint was detected at two sites.
Temporal Representation: | Samples were collected between October 2001 through October 2002. Samples were collected October 9, 2001 at Vineyard; October. 28, 2002 at Highway 33, Vineyard, and 100 feet upstream of the Vineyard Lane Bridge; and May 29, 2002 at Vineyard.
Environmental Conditions: | San Joaquin River Sub-Basin; located in Stanislaus County, on the west side of the valley floor. This stream reaches the San Joaquin River downstream of the Merced River mouth and upstream of the Tuolumne River. The sampling sites are located at Del Puerto Creek at Vineyard, Del Puerto Creek at Rogers Road, Del Puerto Creek at Highway 33, Del Puerto Creek 100 feet upstream of Vineyard Lane bridge.
QAPP Information: | SWAMP QAPP. None of the samples displaying toxicity in the survival endpoint and considered as part of the data assessed had any associated QA qualifiers. Samples also were collected from Del Puerto Creek at Rogers Road on 10/28/04; however, these samples did not meet the QA requirements, and were not considered here.
QAPP Information Reference(s):
LOE ID: | 2783
Pollutant: | Pyrethroids
LOE Subgroup: | Pollutant-Water
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Asses Water Quality: | Toxicity Identification Evaluations (TIEs) were conducted on samples collected from Del Puerto Creek at Vineyard on 5/29/2002 and 9/11/2002. Toxicity was increased by the following TIE manipulations: addition of PBO and decrease of test temperatures, both suggesting evidence of pyrethroid pesticides (Central Valley Regional Water Quality Control Board, 2002).
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | Waters are to remain free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal or aquatic life. Toxicity may be caused by a single substance or the interactive effect of multiple substances (Region 5 Basin Plan, September, 1998)
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: |
Temporal Representation: |
Environmental Conditions: |
QAPP Information: | QA Info Missing
QAPP Information Reference(s):