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

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name: Santa Clara River Reach 11 (Piru Creek, from confluence with Santa Clara River Reach 4 to gaging station below Santa Felicia Dam)
Water Body ID: CAR4034100020050918185447
Water Body Type: River & Stream
 
DECISION ID
9318
 
Pollutant: Specific Conductance
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.

One line of evidence is 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 for 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. 12 of 13 samples exceeded the Agricultural Water Quality Goals published by the Food and Agriculture Organization of the United Nations 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 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 9318
 
LOE ID: 8757
 
Pollutant: Specific Conductance
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 12
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: 12 of 13 samples exceeded the Agricultural Water Quality Goals published by the Food and Agriculture Organization of the United Nations for specific conductance. Water quality samples were taken for specific conductance in accordance with regional SWAMP Monitoring parameters.
Data Reference: Surface Water Ambient Monitoring Program data for all watersheds in the Los Angeles Region 2001-2005.
 
Water Quality Objective/Criterion: The Agricultural Water Quality Goals published by the Food and Agriculture Organization of the United Nations is 700 umhos/cm for Specific Conductance.
Objective/Criterion Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The Los Angeles Regional Board sampled and measured specific conductance at Santa Clara River Reach 11 at the following ten monitoring stations :
403STC009 (Lat. 34.53338) (Long. -118.75854),
403STC017 (Lat. 34.68799) (Long. -118.902479),
403STC021 (Lat. 34.64754) (Long. -119.06954),
403STC025 (Lat. 34.66521) (Long. -119.0517),
403STC069 (Lat. 34.68243) (Long. -119.0223),
403STC071 (Lat. 34.68281) (Long. -118.843),
403STC076 (Lat. 34.42366) (Long. -118.76392),
403STC083 (Lat. 34.62801) (Long. -118.7455),
403STC085 (Lat. 34.642) (Long. -119.0723), and
403STC093 (Lat. 34.708611) (Long. -118.975).
Temporal Representation: Grab samples were taken from 11/15/2001 to 06/23/2003.
Environmental Conditions:
QAPP Information: Data was collected in compliance with the sampling and monitoring procedures detailed in State of California's Surface Water Ambient Monitoring Program Quality Assurance Management Plan.
QAPP Information Reference(s): Quality Assurance Management 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
9317
 
Pollutant: Total Dissolved Solids
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.

One line of evidence is 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 for 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 13 samples exceeded the Basin Plan reach specific water quality criterion for total dissolved solids 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 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 9317
 
LOE ID: 8756
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 13
Number of Exceedances: 8
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight of 13 samples exceeded the Basin Plan objectives for TDS. Water quality samples were taken for TDS in accordance with regional SWAMP Monitoring parameters.
Data Reference: Surface Water Ambient Monitoring Program data for all watersheds in the Los Angeles Region 2001-2005.
 
Water Quality Objective/Criterion: The Basin Plan lists a specific water quality objectives for Santa Clara River Reach 11 of 800 mg/L for total dissolved solids (TDS).
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
  Basin Plan Amendments to the Water Quality Control Plan Los Angeles Region R4 Basin Plan as of 02/02/2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The Los Angeles Regional Board sampled and measured specific conductance at Santa Clara River Reach 11 at the following ten monitoring stations :
403STC009 (Lat. 34.53338) (Long. -118.75854),
403STC017 (Lat. 34.68799) (Long. -118.902479),
403STC021 (Lat. 34.64754) (Long. -119.06954),
403STC025 (Lat. 34.66521) (Long. -119.0517),
403STC069 (Lat. 34.68243) (Long. -119.0223),
403STC071 (Lat. 34.68281) (Long. -118.843),
403STC076 (Lat. 34.42366) (Long. -118.76392),
403STC083 (Lat. 34.62801) (Long. -118.7455),
403STC085 (Lat. 34.642) (Long. -119.0723), and
403STC093 (Lat. 34.708611) (Long. -118.975).
Temporal Representation: Grab samples were taken from 11/15/2001 to 06/23/2003.
Environmental Conditions:
QAPP Information: Data was collected in compliance with the sampling and monitoring procedures detailed in State of California's Surface Water Ambient Monitoring Program Quality Assurance Management Plan.
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)