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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Temecula Creek
Water Body ID: CAR9025100020011025111323
Water Body Type: River & Stream
 
DECISION ID
5729
 
Pollutant: Nitrogen
Final Listing Decision: 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
Reason for Delisting: Flaws in original listing
Impairment from Pollutant or Pollution: Pollutant
 
Weight of Evidence: This pollutant is being considered for removal from the section 303(d) list under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

One line of evidence are available in the administrative record to assess pollutant. Nineteen of 160 samples exceed the Basin Plan water quality objective for nitrogen.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) list.

The reason for removal is that nitrogen is a conventional pollutant, not a toxic pollutant, so the criteria for listing change.

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. Nineteen of 160 samples exceed the Basin Plan water quality objective for nitrogen and this does not exceed the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
RWQCB Board Decision / Staff Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
SWRCB Board Decision / Staff Recommendation:
 
USEPA Decision:
 
 
Lines of Evidence (LOEs) for Decision ID 5729
 
LOE ID: 3159
 
Pollutant: Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 160
Number of Exceedances: 19
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Ranch California Water District from 1999 to 2002. Nineteen of 160 samples were in exceedance (RCWD, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters, enclosed bays and estuaries, coastal lagoons, and ground waters and all beneficial uses, analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek.
Temporal Representation: Samples were collected 4-5 times per month from 03/1999 to 04/2002
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
DECISION ID
17915
 
Pollutant: Benthic Community Effects
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: Pollution
 
Weight of Evidence: Benthic Community Effects is being considered for placement on the section 303(d) list under sections 3.9 and 3.2 of the Listing Policy. Under section 3.9, an additional line of evidence associating the Benthic Community Effects with a water or sediment concentration of pollutants is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this indicator. 4 of 7 samples exceeded the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this water segment 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. 4 of 7 samples exceeded the Index of Biological Integrity (IBI) value of "poor" water quality for this area 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 17915
 
LOE ID: 26472
 
Pollutant: Benthic Community Effects
LOE Subgroup: Adverse Biological Responses
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 4
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Seven samples of IBI data were taken from May 1998 to November 2000 at one sampling site. Of the total number of samples, four samples exceeded the IBI impairment threshold.
Data Reference: Fish and Game IBI Data
 
Water Quality Objective/Criterion: From the San Diego Basin Plan the objective is: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. (SDRWQCB, 1995)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin (9).
 
Evaluation Guideline: The Index of Biological Integrity (IBI) is an analytical tool that can be used to assess the biological and physical condition of streams and rivers within a zero to one hundred scoring range: Very Poor 0-19, Poor 20-39, Fair 40-59, Good 60- 79, Very Good 80-100. The IBI score of 39 was set as an impairment threshold because it is a statistical criterion of two standard deviations below the mean reference site score which defines the boundary between 'fair' and 'poor' IBI creek conditions. (Ode, p. 9)
Guideline Reference: "A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams". Environmental Management. Volume 35, number 1 (2005): 1-13.
 
Spatial Representation: Samples were collected at one site: 902TCI15x on Temecula Creek.
Temporal Representation: Sampling occurred during two to three events from May 1998 to November 2000.
Environmental Conditions:
QAPP Information: Quality Control for collection and identification was conducted in accordance with the Quality Assurance Project Plan for the California Stream Bioassessment Procedure and the State of California, California Monitoring an Assessment Program: "CMAP", Quality Assurance Project Plan.
QAPP Information Reference(s): State of California, California Monitoring and Assessment Program: "CMAP".
  Quality Assurance Project Plan for the California Stream Bioassessment Procedure
  The San Diego Stream Team Quality Assurance Project Plan
 
DECISION ID
16918
 
Pollutant: Fecal Coliform
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Weight of Evidence: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Four of the seven samples exceed the Basin Plan water quality objective for Fecal coliform.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Four of the seven samples exceed the Basin Plan water quality objective for Fecal coliform 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 16918
 
LOE ID: 7403
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Four out of seven samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through May 2006.
Data Reference: Watershed Annual Progress Report 2004 and 2005. Watershed Annual Progress Report 2005 and 2006.
 
Water Quality Objective/Criterion: From the Basin Plan, no more than 10% of the samples during any 30-day period for waters designated for contact recreation shall exceed 400 per 100 ml (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin (9).
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek below Pala Road, lat/long: 33°28’26.4” N/117°07’46.1” W.
Temporal Representation: Four samples are collected per monitoring year. Samples were collected from October 2004 through May 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, three samples represent wet weather and two samples represent dry weather. However, one sampling event in both the 2004-2005 and 2005-2006 monitoring year did not analyze for all constituents.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
DECISION ID
16596
 
Pollutant: 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: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff--Industrial Permitted
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 3.6 of the Listing Policy. Under section 3.6 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. Three of seven of the samples exceed the water quality objective for 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. Three of seven of the samples exceed the Basin Plan water quality objective for toxicity 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 16596
 
LOE ID: 7511
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Hyalella Azteca-
Three out of seven samples were found to have acute toxicity by the Hyalella Azteca growth/survival test.
Selenastrum capricornutum-
None of seven samples were found to have toxicity by the green alage, Selenastrum capricornutum, growth test. Toxicity results were in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through March 2006.
Data Reference: Watershed Annual Progress Report 2004 and 2005. Watershed Annual Progress Report 2005 and 2006.
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin (9).
 
Evaluation Guideline: Samples were found to exhibit toxicity when the No Observed Effect Concentration (NOEC) or median lethal concentration (LC50) for any given species was estimated to be less than 100% of the test sample concentration.
Guideline Reference: Waste Discharge Requirements for Discharges of Urban Runoff From the Municipal Separate Storm Sewer Systems Draining the Watersheds of the County of San Diego, the Incorporated Cities of San Diego, the San Diego Unified Port District, and the San Diego County Regional Airport. Order No. R9-2007-0001.
 
Spatial Representation: Samples were collected at Temecula Creek below Pala Road, lat/long: 33°28’26.4” N/117°07’46.1” W.
Temporal Representation: Three to four samples are collected per monitoring year. Samples were collected from October 2004 through March 2006.
Environmental Conditions: Toxicity testing is conducted on all storm event samples (at least three annually).
QAPP Information: Quality control conducted in compliance with the Riverside County's quality assurance plan.
QAPP Information Reference(s): Watershed Annual Progress Report 2004 and 2005. Watershed Annual Progress Report 2005 and 2006.
 
DECISION ID
5769
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2006)
Revision Status Original
Impairment from Pollutant or Pollution: Pollution
 
Weight of Evidence: 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 the single line of evidence in the record to assess this pollutant consists of bioassessment data. This information on its own is insufficient to determine with the confidence and power required by the Listing Policy since this data is not associated with water or sediment concentrations of pollutants (Policy Section 3.9).
 
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 it cannot be determined if applicable water quality standards are not being exceeded.
 
SWRCB Board Decision / Staff Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are exceeded.
 
USEPA Decision:
 
 
Lines of Evidence (LOEs) for Decision ID 5769
 
LOE ID: 3157
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Data were collected for the San Diego Regional Water Quality Control Board 1999 Biological Assessment Annual Report. Physical habitat scores at TC-I-15 ranged from 109 to 136, higher scores compared to other sampled waterbodies. BMI scores at TC-I-15 were either slightly above or slightly below average, compared to other sampled waterbodies. (SDRWQCB, 1999A).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek, 5 riffles immediately downstream of I-15 (TC-I-15).
Temporal Representation: Samples were collected in May, September, November 1998 and May 1999.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
DECISION ID
5731
 
Pollutant: Boron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2006)
Revision Status Original
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 are available in the administrative record to assess this pollutant. None of 160 of the samples exceed the Basin Plan water quality objective for Boron.

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 160 of the samples exceed the Basin Plan water quality objective for Boron 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 5731
 
LOE ID: 3161
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 160
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Rancho California Water District from 1999 to 2002. None of the 160 samples were in exceedance (RCWD, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for boron is 0.75 mg/L. This concentration is not to be exceeded more than 10% of the time during any one year period.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek.
Temporal Representation: Samples were collected 4-5 times per month from 03/31/1999 to 04/17/2002.
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
DECISION ID
16917
 
Pollutant: Escherichia coli (E. Coli)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Weight of Evidence: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Four of the seven samples exceed the Basin Plan water quality objective for Escherichia coli.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Four of the seven samples exceed the Basin Plan water quality objective for Escherichia coli 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 16917
 
LOE ID: 7152
 
Pollutant: Escherichia coli (E. Coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Four out of seven samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through May 2006.
Data Reference: Watershed Annual Progress Report 2004 and 2005. Watershed Annual Progress Report 2005 and 2006.
 
Water Quality Objective/Criterion: The maximum E. coli level for moderately or lightly used areas is 406 colonies per 100 ml ( RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin (9).
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek below Pala Road, lat/long: 33°28’26.4” N/117°07’46.1” W.
Temporal Representation: Four samples are collected per monitoring year. Samples were collected from October 2004 through May 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, three samples represent wet weather and two samples represent dry weather. However, one sampling event in both the 2004-2005 and 2005-2006 monitoring year did not analyze for all constituents.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
DECISION ID
5730
 
Pollutant: Surfactants (MBAS)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2006)
Revision Status Original
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. None of 160 of the samples exceed the Basin Plan water quality objective for surfactants.

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 160 of the samples exceed the Basin Plan water quality objective for surfactants 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 5730
 
LOE ID: 3160
 
Pollutant: Surfactants (MBAS)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 160
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Data were collected by Rancho California Water District from 1999 to 2002. None of the 160 samples were in exceedance (RCWD, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for MBAS is 0.5 mg/L. This concentration is not to be exceeded more than 10% of the time during any one year period.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek.
Temporal Representation: Samples were collected 4-5 times per month from 03/31/1999 to 04/17/2002.
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
DECISION ID
5768
 
Pollutant: Turbidity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2006)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Weight of Evidence: One line of evidence is available in the administrative record to assess this pollutant. A single sample was collected and it did not exceed the Basin Plan criteria, but the number of samples is insufficient to determine with the confidence and power required by 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.
 
RWQCB Board Decision / Staff Recommendation: No new data were assessed for 2008. The decision has not changed.
 
SWRCB Board Decision / Staff Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are exceeded.
 
USEPA Decision:
 
 
Lines of Evidence (LOEs) for Decision ID 5768
 
LOE ID: 3156
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by RWQCB 9 in 1998. One sample was collected and was not in exceedance (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters with a municipal beneficial use, the WQO for turbidity is 5.0 ntu.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected Temecula Creek east of the confluence, west of I-15.
Temporal Representation: Samples were collected on 06/09/1998.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
DECISION ID
16594
 
Pollutant: Chlorpyrifos
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Original
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 line of evidence is available in the administrative record to assess this pollutant. Seven of nine of the samples exceed the Basin Plan water quality objective for Chlorpyrifos.

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. Seven of nine of the samples exceed the Basin Plan water quality objective for Chlorpyrifos 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 16594
 
LOE ID: 6462
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 7
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Seven out of nine samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through May 2006.
Data Reference: Watershed Annual Progress Report 2004 and 2005. Watershed Annual Progress Report 2005 and 2006.
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin (9).
 
Evaluation Guideline: The 4-day average concentration of chlorpyrifos in freshwater is 0.014 ug/L. The 1-hour average concentration of chlorpyrifos in freshwater is 0.025 ug/L according to Siepmann and Finlayson, 2000; 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 at Temecula Creek below Pala Road, lat/long: 33°28’26.4” N/117°07’46.1” W.
Temporal Representation: Four to six samples are collected per monitoring year. Samples were collected from October 2004 through May 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, three samples represent wet weather and two samples represent dry weather. However, one sampling event in the 2004-2005 monitoring year did not analyze for all constituents.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
DECISION ID
16595
 
Pollutant: Copper
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Original
Sources: Source Unknown | Urban Runoff/Storm Sewers
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 line of evidence is available in the administrative record to assess this pollutant. Four of eight of the samples exceed the CTR water quality objective for copper.

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. Four of eight of the samples exceed the CTR water quality objective for 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 16595
 
LOE ID: 6515
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Four of eight samples exceeded the warm freshwater habitat water quality objective for Copper from results in the Riverside County Flood Control and Water Conservation annual progress reports from 2005 and 2006. The eight samples were collected between October 2004 and May 2006.
Data Reference: Watershed Annual Progress Report 2004 and 2005. Watershed Annual Progress Report 2005 and 2006.
 
Water Quality Objective/Criterion: From the CTR, the dissolved copper chronic criterion is 3.1 ppb and the acute criterion is 4.8 ppb, but these criteria may vary depending upon hardness of the sample (U.S. EPA, 2000).
Objective/Criterion Reference: Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic Pollutants for the State of California; Rule. 40 CFR Part 131. U.S. Environmental Protection Agency, Region IX, Water Division, San Francisco, CA.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek below Pala Road, lat/long: 33°28’26.4” N/117°07’46.1” W.
Temporal Representation: Four to six samples are collected per monitoring year. Samples were collected from October 2004 through May 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, three samples represent wet weather and two samples represent dry weather. However, one sampling event in both the 2004-2005 and 2005-2006 monitoring years did not analyze for all constituents.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
DECISION ID
5728
 
Pollutant: Phosphorus
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: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Weight of Evidence: This pollutant is being considered for removal from the section 303(d) list under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess pollutant. One-hundred thirty-nine of 160 samples exceed the Basin Plan water quality objective for phosphorus.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One-hundred thirty-nine of 160 samples exceeded the Basin Plan water quality objective for phosphorus and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
RWQCB Board Decision / Staff Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
SWRCB Board Decision / Staff Recommendation:
 
USEPA Decision:
 
 
Lines of Evidence (LOEs) for Decision ID 5728
 
LOE ID: 3158
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 160
Number of Exceedances: 139
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by the Rancho California Water District in 1999-2002. There were 139 of 160 samples that were in exceedance (RCWD, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters - streams and other flowing waters
and all beneficial uses, the WQO for total phosphorus is 0.1 mg/L. This appears to be desired goal in order to prevent plant nuisance in streams and other flowing waters; not to be exceeded more than 10% of the time.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: Use unless studies of the specific water body in question clearly show that water quality objective changes are permissible and changes are approved by the Regional Board.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: Samples were collected at Temecula Creek.
Temporal Representation: Samples were collected 4-5 times per month from 03/31/1999 to 04/17/2002.
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
DECISION ID
5767
 
Pollutant: Total Dissolved Solids
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: Unknown Nonpoint Source | Unknown Point Source | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: 2019
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. One hundred fifty-seven of the 161 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. One hundred fifty-seven of the 161 samples exceed the Basin Plan 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 5767
 
LOE ID: 3154
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by RWQCB9 in 1998. One sample was collected and was in exceedance.
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for TDS is 500 mg/L. This concentration is not to be exceeded more than 10% of the time during any one year period.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek east of the confluence, west of I-15.
Temporal Representation: Samples were collected on 06/09/1998.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment. QA=?
QAPP Information Reference(s):
 
LOE ID: 3155
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 160
Number of Exceedances: 156
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Rancho California Water District from 1999 to 2002. There were 156 of 160 samples that were in exceedance (RCWD, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for TDS is 500 mg/L. This concentration is not to be exceeded more than 10% of the time during any one year period.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Temecula Creek.
Temporal Representation: Samples were collected 4-5 times per month from 03/31/1999 to 04/17/2002.
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):