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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: San Luis Rey River, Lower (west of Interstate 15)
Water Body ID: CAR9031100020011005104327
Water Body Type: River & Stream
 
DECISION ID
128035
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Indicator Bacteria
Final Listing Decision: Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Reason for Delisting: Applicable WQS attained; due to change in WQS
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the section 303(d) list under section 4.3 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. Sixteen of the 111 samples exceeded the STV threshold for E. coli.

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.
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. Sixteen of 111 samples exceeded the E. coli water quality threshold for the protection of REC-1, 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.

The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For E. coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For E. coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76148
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 5
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 5 of 8 samples exceed the criterion for Coliform, Fecal.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In waters designated for water contact recreation (REC I), the fecal coliform concentration shall not exceed 400 MPN/100 ml.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected over the time period 6/3/2003-5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 220725
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 44
Number of Exceedances: 12
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 12 of the 44 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial for all saline waters, is a Statistical Threshold Value (STV) of Enterococci of 110 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): SLR-010
Temporal Representation: The samples were collected between the days of 2010-11-20 and 2018-10-06 .
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 220686
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 32
Number of Exceedances: 9
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 9 of the 32 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): SLR25
Temporal Representation: The samples were collected between the days of 2016-02-01 and 2018-09-06 .
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 220614
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 36
Number of Exceedances: 3
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 3 of the 36 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): SLR-040
Temporal Representation: The samples were collected between the days of 2010-11-20 and 2018-06-02 .
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 220613
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 19
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 2 of the 19 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): SLR-030
Temporal Representation: The samples were collected between the days of 2010-11-20 and 2018-06-02 .
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 220615
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 14
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 1 of the 14 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): SLR-050
Temporal Representation: The samples were collected between the days of 2010-11-20 and 2018-04-07 .
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76203
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 8 samples exceed the criterion for Coliform, Total.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxicsubstances in concentrations which are toxic to,or which produce detrimental physiologicalresponses in human, plant, animal, or indigenousaquatic life (Basin Plan).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In waters designated for water contact recreation (REC I), the total coliform concentration shall not exceed 10000 MPN/100 ml (CDPH 2006).
Guideline Reference: Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected over the time period 6/3/2003-5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7495
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 8
 
Data and Information Type: PWS pathogen monitoring (ambient water)
Data Used to Assess Water Quality: Eight of fifteen samples collected exceed the water quality objective according to results in the San Diego County Municipal Copermittees Report, 2007. Samples were collected one to four times a year from 2001-2006.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
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 colonies per 100 ml.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station located near the lower boundary of the watershed in Oceanside, under the Benet Road Bridge, north of Highway 76.
Temporal Representation: Samples were collected one to four times a year from 2001-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7494
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 15
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All fifteen samples collected exceed the water quality objective according to results in the San Diego County Municipal Copermittees Report, 2007. Samples were collected one to four times a year from 2001-2006.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, the most stringent of the US EPA bacteriological criteria for enterococcus sets a maximum limit at 61 colonies per 100mL (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at the mass loading station located near the lower boundary of the watershed in Oceanside, under the Benet Road Bridge, north of Highway 76.
Temporal Representation: Samples were collected one to four times a year from 2001-2006.
Environmental Conditions: Samples were collected during wet weather.
base flow.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76132
 
Pollutant: Enterococcus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 7
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 7 of 8 samples exceed the criterion for Enterococci.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Samples shall not exceed 61 organisms per 100 ml for enterococcus in waters designated for REC I beneficial use (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected over the time period 6/3/2003-5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 128035, Indicator Bacteria
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233434
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 10
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Santa Margarita River (Lower) to determine beneficial use support and the results are as follows: 1 of the 10 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): SLR-MLS
Temporal Representation: The samples were collected between the days of 2017-01-18 and 2018-04-05 .
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
126463
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Benthic Community Effects
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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2025
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects is being considered for delisting from the CWA Section 303(d) list under sections 4.9 and 4.1 of the Listing Policy.

Based on the readily available data and information, the weight of evidence does not provide sufficient justification for removing Benthic Community Effects in this water segment from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Pursuant to section 4.9 of the Listing Policy, the water exhibits significant degradation in biological populations and/or communities as compared to reference site(s) using the California Stream Condition Index. 29 of 29 benthic-macroinvertebrate samples during the 2020 Listing Cycle exceed the California Stream Condition Index (CSCI) impairment threshold. Three samples were same-day replicates. These data indicate that the waterbody remains impaired for Benthic Community Effects.
4. Pursuant to section 4.9 of the Listing Policy, the water segment has associated pollutant(s) samples that exceed water quality objectives.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are being met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144768
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 9 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145856
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 37
Number of Exceedances: 22
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 22 of 37 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145842
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 15 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145833
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146194
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146276
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146313
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 11 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146074
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145821
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146004
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145949
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146006
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 48
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 15 of 48 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145931
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 18
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 18 of 23 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146315
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147113
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 8 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147134
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147044
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2013-01-26 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147040
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2012-10-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144174
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144316
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 37
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 13 of 37 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144142
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144256
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144196
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 13 of 15 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144271
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 49
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 5 of 49 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144322
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 9 of 24 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144346
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 6 of 11 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144314
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144123
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 8 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144296
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144214
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144313
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134704
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC01881 )
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134770
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC02905 )
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134760
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 2 samples collected by SWAMP Stream Pollution Trends for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 903SLSLR8 )
Temporal Representation: The samples were collected between the dates of 2011-10-27 and 2012-06-01.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134710
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC00665 )
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134742
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC00857 )
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134766
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 4 samples collected by San Diego Region NPDES for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Growth (Chlorophyll a)
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SLR-TWAS-1 )
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10.
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134751
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 4 samples collected by San Diego Region NPDES for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Growth (Chlorophyll a)
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SLR-TWAS-2 )
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10.
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC01689 )
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134756
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 6 samples collected by SWAMP Stream Pollution Trends for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 903SLRRBB )
Temporal Representation: The samples were collected between the dates of 2013-07-11 and 2018-05-03.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144516
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140546
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Bifenthrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2013-01-26 and 2013-01-26
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140979
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140841
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140886
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141382
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140724
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140933
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141156
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 79486
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 28
Number of Exceedances: 24
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Of 28 total samples collected at 5 stations, 24 had scores below the 0.79 threshold, and therefore are exceeding the water quality objective for the aquatic life beneficial use. 1 sample was flagged and not included due to low organism counts.
Data Reference: Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
  Bioassessment Data for Various Pollutants from Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
  Region 9 CSCI Scores & Water Body Information
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: The samples were collected at stations 903SLRR-MLS SMC00153 903SLRR-MR 903SLR-TWAS-1 SMC01717
Temporal Representation: The samples were from 2001 to 2009.
Environmental Conditions:
QAPP Information: The data was collected under the Southern California Regional Watershed Monitoring Program Bioassessment Quality Assurance Project Plan and the County of San Diego NPDES MS4 Copermittees Receiving Waters Monitoring and Reporting Program
QAPP Information Reference(s): Bioassessment Data for Various Pollutants from Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
QAPP Information Reference(s): Quality Assurance Project Plan for SWAMP Bioassessment and Freshwater Bioassessment.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76168
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 2 of 24 samples exceed the criterion for Malathion.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/8/2002-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7374
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All four samples exceed the water quality objective according to results in the Surface Water Ambient Monitoring Program Report, 2007. Samples were collected at each site on the following four dates, May 18-19, 2004, September 13- 14, 2004, March 1- 2, 2005, April 18- 20, 2005.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at San Luis Rey River 8 (station id: 903SLSLR8 lat/long: 33.21494/-117.36837), located on the main stem of the San Luis Rey River.
Temporal Representation: Samples were collected at each site on the following four dates, May 18-19, 2004, September 13- 14, 2004, March 1- 2, 2005, April 18- 20, 2005.
Environmental Conditions: The first two sampling events occurred during declining and minimum base flow respectively. The third occurred between storm events and the fourth during high base flow.
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7348
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 15
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: All fifteen samples exceed the water quality objective according to results in the San Diego County Municipal Copermittees Report, 2007. Samples were collected one to four times a year from 2001-2006.
Data Reference: Water Quality Control Plan for the San Diego Basin
  Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station located near the lower boundary of the watershed in Oceanside, under the Benet Road Bridge, north of Highway 76.
Temporal Representation: Samples were collected one to four times a year from 2001-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 21182
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Three water samples were collected at San Luis Rey River station 903SLSLR2 May 2004, September 2004, March 2005, and April 2005. Two of three samples showed excessive selenium concentrations but one sample was "estimated" according to results in California's Surface Water Ambient Monitoring Program Report, 2007.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic
substances in concentrations that are toxic to, or
that produce detrimental physiological responses
in human, plant, animal, or aquatic life (RWQCB, 2007).
CTR Freshwater Chronic (CCC) 5 ug/L. (U.S. EPA, 2000).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Water samples were collected at San Luis Rey River station 903SLSLR2.
Temporal Representation: Samples were collected on May 2004, September 2004, March 2005, and April 2005.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 23502
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 5
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Five of eight samples exceed the water quality objective according to results in the Surface Water Ambient Monitoring Program Report, 2007. Samples were collected at each site on the following four dates, May 18-19, 2004, September 13-14, 2004, March 1-2, 2005, April 18- 20, 2005.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses. (RWQCB, 2007)
A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. These values are not to be exceeded more than 10% of the time 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. 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. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at monitoring station San Luis Rey River 8 (station id: 903SLSLR8 lat/long: 33.21494/-117.36837).
Temporal Representation: Samples were collected at each site on the following four dates, May 18-19, 2004, September 13-14, 2004, March 1-2, 2005, April 18- 20, 2005.
Environmental Conditions: The first two sampling events occurred during declining and minimum base flow respectively. The third sample occurred between storm events and the fourth during high base flow.
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7355
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 13
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Thirteen of fifteen samples exceed the water quality objective according to the results in San Diego County Municipal Copermittees Annual Progress Report, 2007. Samples were collected one to four times a year from 2001-2006.
Data Reference: Water Quality Control Plan for the San Diego Basin
  Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses. (RWQCB, 2007)
A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. These values are not to be exceeded more than 10% of the time 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. 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. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station located near the lower boundary of the watershed in Oceanside, under the Benet Road Bridge, north of Highway 76.
Temporal Representation: Samples were collected one to four times a year from 2001-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76204
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Twenty-seven samples were collected to test for toxicity. Seven of the 27 samples exhibited statistically significant toxicity. The toxicity tests that exhibited significant toxicity included survival of Hyalella azteca, growth of Selenastrum capriconutum and reproduction of Ceriodaphnia dubia.
Data Reference: Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at stations 903SLR-MLS and 903SLR-TWAS-1, San Luis Rey River.
Temporal Representation: The samples were collected from 2001 to 2008.
Environmental Conditions:
QAPP Information: The data was collected under the County of San Diego Co-Permittees Receiving Waters Urban Runoff Monitoring and Reporting Program (Order No. 2007-01). Data quality is good.
QAPP Information Reference(s): e-mail clarifying QAPP information
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7493
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Selenastrum capricornutum-
Eight samples were collected and three samples show significant toxicity levels (SL) as determined by the Selenastrum capricornutum growth test.

Ceriodaphnia dubia-
Eight samples were collected and two samples show significant toxicity levels (SL) as determined by the Ceriodaphnia dubia survival/reproductive test.

Hyalella azteca-
Eight samples were collected and none show significant toxicity levels (SL) as determined by at least one of the Hyalella azteca survival/growth test according to results in the Surface Water Ambient Monitoring Program Report, 2007. Samples were collected at each site on the following four dates, May 18-19, September 13-14, 2004, March 1-2, April 18 and April 20, 2005.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
  Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
SWAMP Data: Non-SWAMP
 
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
 
Evaluation Guideline: Waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: Samples were collected at monitoring station San Luis Rey River 2 and San Luis Rey River 8.
Temporal Representation: Samples were collected at each site on the following four dates, May 18-19, September 13-14, 2004, March 1-2, April 18 and April 20, 2005.
Environmental Conditions:
QAPP Information: Quality control for the chemical anaylsis of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 23503
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Selenastrum capricornutum-
One of fifteen samples collected were found to be toxic as determined by the Selenastrum capricornutum growth test, Ceriodaphnia dubia survival/reproductive test.

Ceriodaphnia dubia-
Two of fifteen samples collected were found to be toxic as determined by the Ceriodaphnia dubia survival/reproductive test.

Hyalella azteca -
None of the fifteen samples collected were found to be toxic as determined by the Hyalella azteca survival test according to results in the San Diego County Municipal Copermittees Report, 2007.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
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
 
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 mass loading station under the Benet Rd bridge north of highway 76 on the San Luis Rey River.
Temporal Representation: Samples were collected at from 2001 through 2006
Environmental Conditions:
QAPP Information: Samples were collected in compliance with Weston's quality assurance plan.
QAPP Information Reference(s): Weston Solutions, 2004. Quality Management Manual. March 2004 (Revised December 2009).
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215850
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903SLRMBD to determine beneficial use support and the results are as follows: 3 of 3 samples exceeded the threshold. CSCI scores were from 0.36 to 0.76 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903SLRMBD
Temporal Representation: Samples were collected from 5/11/2015 to 6/19/2018.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program (401)
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215884
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC01689 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.30015228 to 0.30015228 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC01689
Temporal Representation: Samples were collected from 7/5/2012 to 7/5/2012.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215893
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC02933 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.74665557 to 0.74665557 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC02933
Temporal Representation: Samples were collected from 6/1/2010 to 6/1/2010.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215876
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903S00665 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.52167578 to 0.52167578 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903S00665
Temporal Representation: Samples were collected from 7/27/2011 to 7/27/2011.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215867
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903M20230 to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the threshold. CSCI scores were from 0.52195746 to 0.60212715 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903M20230
Temporal Representation: Samples were collected from 5/8/2018 to 5/8/2018.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215877
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903S00857 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.43263907 to 0.43263907 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903S00857
Temporal Representation: Samples were collected from 7/13/2011 to 7/13/2011.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215858
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903SLRMBU to determine beneficial use support and the results are as follows: 3 of 3 samples exceeded the threshold. CSCI scores were from 0.44 to 0.59 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903SLRMBU
Temporal Representation: Samples were collected from 4/2/2015 to 6/20/2018.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program (401)
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215849
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903SLRMLS to determine beneficial use support and the results are as follows: 4 of 4 samples exceeded the threshold. CSCI scores were from 0.3382 to 0.6816 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903SLRMLS
Temporal Representation: Samples were collected from 2011 to 2017.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215866
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903STWAS2 to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the threshold. CSCI scores were from 0.4423 to 0.6625 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903STWAS2
Temporal Representation: Samples were collected from 2011 to 2013.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215859
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903STWAS1 to determine beneficial use support and the results are as follows: 3 of 3 samples exceeded the threshold. CSCI scores were from 0.5632 to 0.6898 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903STWAS1
Temporal Representation: Samples were collected from 2011 to 2015.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215885
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC02457 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.59750505 to 0.59750505 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC02457
Temporal Representation: Samples were collected from 5/31/2010 to 5/31/2010.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215886
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC02905 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.4370028 to 0.4370028 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC02905
Temporal Representation: Samples were collected from 7/9/2013 to 7/9/2013.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215868
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC01881 to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the threshold. CSCI scores were from 0.35483598 to 0.35893211 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC01881
Temporal Representation: Samples were collected from 7/9/2013 to 7/9/2013.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215875
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903M20214 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.5565705 to 0.5565705 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903M20214
Temporal Representation: Samples were collected from 5/8/2018 to 5/8/2018.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program
QAPP Information Reference(s): Quality Assurance Project Plan for Southern California Regional Watershed Monitoring Program Bioassessment, Version 1.0, and Freshwater Bioassessment from Weston Solutions.
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 215857
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 903SLRMBR to determine beneficial use support and the results are as follows: 3 of 3 samples exceeded the threshold. CSCI scores were from 0.32 to 0.53 .
Data Reference: California Stream Condition Index Scores for the 2020 Integrated Report
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.  
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 903SLRMBR
Temporal Representation: Samples were collected from 4/2/2015 to 6/19/2018.
Environmental Conditions:
QAPP Information: The data was collected under a permit required receiving waters monitoring and reporting program (401)
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144509
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2014-11-21 and 2015-05-05
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144510
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144753
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144597
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144602
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144647
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144760
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144367
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR2)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2018-03-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144531
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLRRBB)
Temporal Representation: The samples were collected between the dates of 2017-05-02 and 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144628
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144885
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144544
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2016-08-20 and 2016-12-10
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144530
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 126463, Benthic Community Effects
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144508
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR1)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2016-01-06
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111498
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Bifenthrin
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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2029
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under sections 4.1 and 4.6 of the Listing Policy. Under sections 4.1 and 4.6, at least one line of evidence is necessary to assess listing status.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Six of six samples exceed the water quality threshold in water. One of 14 samples exceed the threshold for sediment chemistry, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of six samples exceed the water quality threshold in water, 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 not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135745
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135488
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135984
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140561
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140546
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Bifenthrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2013-01-26 and 2013-01-26
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135580
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233416
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River (Lower) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-MLS.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-02-15
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140678
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135818
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227709
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227934
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Bifenthrin. Although a total of 3 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Data for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233411
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for Santa Luis Rey (Lower) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2017-05-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233415
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River (Lower) to determine beneficial use support and results are as follows: 3 of 3 samples exceeded the water quality threshold for Bifenthrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS)
Temporal Representation: The samples were collected between the dates of 2017-01-20 and 2017-05-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111498, Bifenthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135562
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 1 of the 2 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111469
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Chloride
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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Seven lines of evidence are available in the administrative record to assess pollutant. Six of the seven samples exceed the N threshold.

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 CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of seven samples exceeded the threshold and this exceeds 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 met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140841
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140982
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140933
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140828
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140886
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141266
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141156
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140826
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140979
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141153
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140724
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141154
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141342
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141382
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Chloride water quality threshold in this HSA is 250 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111469, Chloride
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 4728
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
132044
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Nitrogen
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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Fifteen lines of evidence are available in the administrative record to assess pollutant. Seventy-eight of the 174 samples exceed the OBJECTIVE.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Seventy-eight of 174 samples exceeded the OBJECTIVE 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.
 
Regional Board Decision 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.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144296
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144313
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144196
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 13 of 15 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144316
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 37
Number of Exceedances: 13
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 13 of 37 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144174
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144271
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 49
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 5 of 49 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7355
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 13
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Thirteen of fifteen samples exceed the water quality objective according to the results in San Diego County Municipal Copermittees Annual Progress Report, 2007. Samples were collected one to four times a year from 2001-2006.
Data Reference: Water Quality Control Plan for the San Diego Basin
  Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses. (RWQCB, 2007)
A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. These values are not to be exceeded more than 10% of the time 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. 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. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station located near the lower boundary of the watershed in Oceanside, under the Benet Road Bridge, north of Highway 76.
Temporal Representation: Samples were collected one to four times a year from 2001-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 23502
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 5
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Five of eight samples exceed the water quality objective according to results in the Surface Water Ambient Monitoring Program Report, 2007. Samples were collected at each site on the following four dates, May 18-19, 2004, September 13-14, 2004, March 1-2, 2005, April 18- 20, 2005.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses. (RWQCB, 2007)
A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. These values are not to be exceeded more than 10% of the time 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. 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. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at monitoring station San Luis Rey River 8 (station id: 903SLSLR8 lat/long: 33.21494/-117.36837).
Temporal Representation: Samples were collected at each site on the following four dates, May 18-19, 2004, September 13-14, 2004, March 1-2, 2005, April 18- 20, 2005.
Environmental Conditions: The first two sampling events occurred during declining and minimum base flow respectively. The third sample occurred between storm events and the fourth during high base flow.
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144322
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 9 of 24 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144314
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144346
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 6 of 11 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144123
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 8 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144214
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144256
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 132044, Nitrogen
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144142
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111488
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Phosphorus
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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Fifteen lines of evidence are available in the administrative record to assess pollutant. Ninety-eight of the 167 samples exceed the threshold.

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 CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Ninety-eight of the 167 samples exceed the threshold, 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.
 
Regional Board Decision 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.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145821
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146074
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145842
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 15 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146313
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 11 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145931
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 18
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 18 of 23 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145833
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146194
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146004
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146315
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146006
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 48
Number of Exceedances: 15
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 15 of 48 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146276
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145856
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 37
Number of Exceedances: 22
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 22 of 37 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145949
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. 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 (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7374
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All four samples exceed the water quality objective according to results in the Surface Water Ambient Monitoring Program Report, 2007. Samples were collected at each site on the following four dates, May 18-19, 2004, September 13- 14, 2004, March 1- 2, 2005, April 18- 20, 2005.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at San Luis Rey River 8 (station id: 903SLSLR8 lat/long: 33.21494/-117.36837), located on the main stem of the San Luis Rey River.
Temporal Representation: Samples were collected at each site on the following four dates, May 18-19, 2004, September 13- 14, 2004, March 1- 2, 2005, April 18- 20, 2005.
Environmental Conditions: The first two sampling events occurred during declining and minimum base flow respectively. The third occurred between storm events and the fourth during high base flow.
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 111488, Phosphorus
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7348
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 15
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: All fifteen samples exceed the water quality objective according to results in the San Diego County Municipal Copermittees Report, 2007. Samples were collected one to four times a year from 2001-2006.
Data Reference: Water Quality Control Plan for the San Diego Basin
  Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses.
Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/L for total phosphorus in streams and other flowing waters. (RWQCB, 2007)
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Samples were collected at the mass loading station located near the lower boundary of the watershed in Oceanside, under the Benet Road Bridge, north of Highway 76.
Temporal Representation: Samples were collected one to four times a year from 2001-2006.
Environmental Conditions: Samples were collected during wet weather.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
 
DECISION ID
111492
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Total Dissolved Solids
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)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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.

Four lines of evidence are available in the administrative record to assess this pollutant. Twenty of the 20 samples exceed the Basin Plan water quality objective for total dissolved solids.

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. Twenty of 20 samples exceed the Basin Plan water quality objective for total dissolved solids, and this exceeds 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 met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147113
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 8 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147064
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 8 of 8 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147044
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2013-01-26 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147020
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 4729
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
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):
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147182
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2012-10-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147168
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2013-01-26 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147134
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111492, Total Dissolved Solids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147040
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 4 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Dissolved Solids water quality threshold in this HSA is 500 mg/L, and this concentration is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2012-10-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111493
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Toxicity
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under sections 4.1 and 4.6 of the Listing Policy. Under sections 4.1 and 4.6, at least one line of evidence is necessary to assess listing status.
Thirteen lines of evidence are available in the administrative record to assess this pollutant. Fourteen of 64 water samples exhibited toxicity, and three of 11 sediment samples exhibited toxicity.
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 CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Fourteen of 64 water samples and three of 11 sediment samples exhibited toxicity, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134704
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC01881 )
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134710
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC00665 )
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134766
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 4 samples collected by San Diego Region NPDES for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Growth (Chlorophyll a)
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SLR-TWAS-1 )
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10.
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134742
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Survival, Ceriodaphnia dubia, for Young/female
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC00857 )
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134756
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 6 samples collected by SWAMP Stream Pollution Trends for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 903SLRRBB )
Temporal Representation: The samples were collected between the dates of 2013-07-11 and 2018-05-03.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76205
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Marine Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Three samples were collected to test for toxicity. Two of the three samples exhibited statistically significant toxicity. The toxicity tests included survival of Eohaustorius estuarius. Each sample is a sediment composites from three different sites.
Data Reference: Data for Various Pollutants from Ambient Bay and Lagoon, 2003-2005.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Assessing the Toxicity of Sediment-associated Contaminants with Estuarine and Marine Amphipods. June 1994. EPA 600/R-94/025
 
Spatial Representation: The samples were collected at 903SLR_2003, 903SLR_2004, and 903SLR_2005. Each of these sample location names consists of a composite from three different sites.
Temporal Representation: The samples were collected in July 2003, 2004, and 2005.
Environmental Conditions:
QAPP Information: The data was collected under the County of San Diego Ambient Bay and Lagoon Monitoring Project 2003-2005. Annual Report for the Receiving Waters and Urban Runoff Monitoring section covered under the San Diego County Municipal National Pollutant Discharge Elimination System (NPDES) Permit (RWQCB-Order NO. R9-2007-0001).
QAPP Information Reference(s): e-mail clarifying QAPP information
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76206
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to test for toxicity. The sample did not exhibit statistically and biologically significant toxicity. The toxicity tests included survival and reproduction of Ceriodaphnia dubia.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Additionally, the biological significance of the sample is evaluated by determining whether the sample response is less than the evaluation threshold
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The sample was collected from site 903_SMC00153, San Luis Rey River, lower.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: This data was collected for the Regional Monitoring Of Southern California's Coastal Watersheds - Stormwater Monitoring Coalition Bioassessment Working Group. CRG Marine Laboratories Quality Assurance Program Document was provided.
QAPP Information Reference(s): e-mail clarifying QAPP information
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76204
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 7
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Twenty-seven samples were collected to test for toxicity. Seven of the 27 samples exhibited statistically significant toxicity. The toxicity tests that exhibited significant toxicity included survival of Hyalella azteca, growth of Selenastrum capriconutum and reproduction of Ceriodaphnia dubia.
Data Reference: Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control.
Guideline Reference: Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. EPA-821-R-02-012
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at stations 903SLR-MLS and 903SLR-TWAS-1, San Luis Rey River.
Temporal Representation: The samples were collected from 2001 to 2008.
Environmental Conditions:
QAPP Information: The data was collected under the County of San Diego Co-Permittees Receiving Waters Urban Runoff Monitoring and Reporting Program (Order No. 2007-01). Data quality is good.
QAPP Information Reference(s): e-mail clarifying QAPP information
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 7493
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Selenastrum capricornutum-
Eight samples were collected and three samples show significant toxicity levels (SL) as determined by the Selenastrum capricornutum growth test.

Ceriodaphnia dubia-
Eight samples were collected and two samples show significant toxicity levels (SL) as determined by the Ceriodaphnia dubia survival/reproductive test.

Hyalella azteca-
Eight samples were collected and none show significant toxicity levels (SL) as determined by at least one of the Hyalella azteca survival/growth test according to results in the Surface Water Ambient Monitoring Program Report, 2007. Samples were collected at each site on the following four dates, May 18-19, September 13-14, 2004, March 1-2, April 18 and April 20, 2005.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
  Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
SWAMP Data: Non-SWAMP
 
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
 
Evaluation Guideline: Waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: Samples were collected at monitoring station San Luis Rey River 2 and San Luis Rey River 8.
Temporal Representation: Samples were collected at each site on the following four dates, May 18-19, September 13-14, 2004, March 1-2, April 18 and April 20, 2005.
Environmental Conditions:
QAPP Information: Quality control for the chemical anaylsis of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 23503
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Selenastrum capricornutum-
One of fifteen samples collected were found to be toxic as determined by the Selenastrum capricornutum growth test, Ceriodaphnia dubia survival/reproductive test.

Ceriodaphnia dubia-
Two of fifteen samples collected were found to be toxic as determined by the Ceriodaphnia dubia survival/reproductive test.

Hyalella azteca -
None of the fifteen samples collected were found to be toxic as determined by the Hyalella azteca survival test according to results in the San Diego County Municipal Copermittees Report, 2007.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
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
 
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 mass loading station under the Benet Rd bridge north of highway 76 on the San Luis Rey River.
Temporal Representation: Samples were collected at from 2001 through 2006
Environmental Conditions:
QAPP Information: Samples were collected in compliance with Weston's quality assurance plan.
QAPP Information Reference(s): Weston Solutions, 2004. Quality Management Manual. March 2004 (Revised December 2009).
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134754
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC01689 )
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134770
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SMC Regional Watershed Monitoring for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia, for Young/female, Ceriodaphnia dubia, for Survival
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SMC02905 )
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09.
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134751
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 4 samples collected by San Diego Region NPDES for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Selenastrum capricornutum, for Growth (Chlorophyll a)
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( SLR-TWAS-2 )
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2011-05-10.
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111493, Toxicity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134760
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 2 samples collected by SWAMP Stream Pollution Trends for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 903SLSLR8 )
Temporal Representation: The samples were collected between the dates of 2011-10-27 and 2012-06-01.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111504
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Alkalinity as CaCO3
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140011
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139854
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139916
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139749
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139818
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139949
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111504, Alkalinity as CaCO3
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139968
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level (USEPA National Recommended Water Quality Criteria Aquatic Life)
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
127746
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Ammonia
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
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA 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.

Thirteen lines of evidence are available in the administrative record to assess this pollutant. Zero of the 112 samples exceed the water quality threshold.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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. Zero of the 112 samples exceed the water quality threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185257
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 37
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 37 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2010-12-18 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184972
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184968
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2013-02-09 and 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184967
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 31
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 31 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-12-18 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184970
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185256
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-12-18 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184976
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185258
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 20
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 20 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-12-18 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185435
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185272
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184969
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-05-10 and 2015-01-07
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 184971
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 127746, Ammonia
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185291
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
115504
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Ammonia (Unionized)
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
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA 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.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of the 71 samples exceed the water quality threshold.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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. Zero of 71 samples exceeded the threshold 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185340
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665).
Temporal Representation: Date for this waterbody was collected over the date range 2011-07-27 to 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185219
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214).
Temporal Representation: Date for this waterbody was collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185341
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857).
Temporal Representation: Date for this waterbody was collected over the date range 2011-07-13 to 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185404
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 35
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 35 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185344
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 21
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 21 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185345
 
Pollutant: Ammonia (Unionized)
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185325
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230).
Temporal Representation: Date for this waterbody was collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185376
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881).
Temporal Representation: Date for this waterbody was collected over the date range 2013-07-09 to 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185418
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905).
Temporal Representation: Date for this waterbody was collected over the date range 2013-07-09 to 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185422
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689).
Temporal Representation: Date for this waterbody was collected over the date range 2012-07-05 to 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185401
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-05-10 to 2015-01-07
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 115504, Ammonia (Unionized)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 185360
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Data for this waterbody was collected over the date range 2013-01-26 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111463
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Anthracene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111463, Anthracene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135204
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Anthracene from MacDonald et al., 2000a which states that the probable effect concentration for Anthrazene is 845 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111464
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Eighteen lines of evidence are available in the administrative record to assess this pollutant. Zero of 53 samples exceed the water quality threshold in water, and zero of five samples exceed the water quality threshold in sediment.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 53 samples exceed the water quality threshold in water, zero of five samples exceed the water quality threshold in sediment, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139966
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139963
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140211
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139884
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140085
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135215
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140212
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140213
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140366
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139833
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140406
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135479
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76289
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Arsenic.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76287
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139812
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140025
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140177
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111464, Arsenic
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139983
 
Pollutant: Arsenic
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater for dissolved arsenic is 0.150 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111466
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Benzo(a)anthracene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111466, Benzo(a)anthracene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135623
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Benz[a]anthrazene from MacDonald et al., 2000a which states that the probable effect concentration for Benz[a]anthrazene is 1050 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111465
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Benzo(a)pyrene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111465, Benzo(a)pyrene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135683
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Benzo[a]pyrene from MacDonald et al., 2000a which states that the probable effect concentration for Benzo[a]pyrene is 1450 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111467
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Cadmium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA 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.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of the 59 samples exceed the water quality threshold.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 59 samples exceed the water quality threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140552
 
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140683
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76300
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 7 samples exceed the criterion for Cadmium.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected 6/3/2003 - 5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76297
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego Dept. of Public Works data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76071
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 26
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed County of San Diego NDPES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 26 samples exceed the criterion for Cadmium.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Cadmium to protect aquatic life in freshwater. The dissolved Cadmium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140859
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140808
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135877
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135783
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Cadmium in 4.98 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140512
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140901
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111467, Cadmium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 140637
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111468
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Chlordane
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111468, Chlordane
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136057
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111468, Chlordane
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 135813
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Chlordane from MacDonald et al., 2000a which states that the probable effect concentration for Chlordane is 17.6 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111470
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Six lines of evidence are available in the administrative record to assess this pollutant. Zero of the 41 samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of three sediment samples exceed the water quality threshold for sediment; this sample size is not sufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA 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. Zero of 41 samples exceeded the water quality threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111470, Chlorpyrifos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136388
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chlorpyrifos. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111470, Chlorpyrifos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 219704
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
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 (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111470, Chlorpyrifos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 219696
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Chlorpyrifos.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (4 day average)(Siepmann and Finlayson 2000).
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 (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111470, Chlorpyrifos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76073
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Chlorpyrifos.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.015 ug/L (Siepmann and Finlayson 2000).
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 (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected over the time period 6/29/2006-5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 111470, Chlorpyrifos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 77827
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 19
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 19 samples exceed the criterion for Chlorpyrifos. Eight sample results were not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater criterion continuous concentration to protect aquatic organisms is 0.014 ug/L (Siepmann and Finlayson 2000).
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 (with minor corrections to significant figures as described in Beaulaurier et al., 2005).
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111470, Chlorpyrifos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136389
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111508
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Chromium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, at least one line of evidence is necessary. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Zero of 51 samples exceed the water quality threshold in water, and zero of four samples exceed the water quality threshold in sediment.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 51 samples exceed the water quality threshold in water, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136157
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141749
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141371
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141745
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141229
 
Pollutant: Chromium
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76089
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed County of San Diego NDPES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Chromium.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Chromium to protect aquatic life in freshwater. The dissolved Chromium criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76088
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego Dept. of Public Works data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chromium.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141163
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141130
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136301
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for Chromium in 111 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111508, Chromium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141183
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111471
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Chrysene (C1-C4)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111471, Chrysene (C1-C4)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136573
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Chrysene from MacDonald et al., 2000a which states that the probable effect concentration for Chrysene is 1290 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111472
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Copper
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, at least one line of evidence is necessary. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of 57 samples exceed the water quality threshold in water, and zero of four samples exceed the water quality threshold in sediment.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 57 samples exceed the water quality threshold, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is not an associated sediment toxicity data as required by Section 3.6 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141781
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141632
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141711
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141721
 
Pollutant: Copper
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141610
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136518
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141499
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141780
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136686
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for copper in 149 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76090
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego Dept. of Public Works data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76112
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed County of San Diego NDPES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 24 samples exceed the criterion for Copper.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Copper to protect aquatic life in freshwater. The dissolved Copper criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111472, Copper
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76092
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected 6/3/2003 - 5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
 
DECISION ID
111505
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Cyfluthrin
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227888
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233436
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Lower) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2017-05-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233435
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Lower) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyfluthrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS)
Temporal Representation: The samples were collected between the dates of 2017-05-09 and 2017-05-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233437
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for Santa Margarita River (Lower) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-MLS.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-02-15
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136453
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136604
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136695
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136436
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141878
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227806
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Cyfluthrin. Although a total of 2 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-TWAS-1).
Temporal Representation: Data for this waterbody was collected over the date range 2007-11-30 to 2008-02-04
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227923
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 141891
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136608
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111505, Cyfluthrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136623
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111507
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Cyhalothrin, Lambda
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227719
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-02-04
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227929
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227720
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142875
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136726
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136878
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136402
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136743
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136417
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142974
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111507, Cyhalothrin, Lambda
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136626
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111499
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227879
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-02-04
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227878
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142123
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136883
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136820
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227860
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136937
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136917
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136955
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142192
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111499, Cypermethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136921
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
127279
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127279, DDD (Dichlorodiphenyldichloroethane)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136941
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127279, DDD (Dichlorodiphenyldichloroethane)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136904
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDD from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDD is 28 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
127297
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127297, DDE (Dichlorodiphenyldichloroethylene)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136717
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127297, DDE (Dichlorodiphenyldichloroethylene)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136715
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDE from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDE is 31.3 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
127373
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127373, DDT (Dichlorodiphenyltrichloroethane)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136808
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127373, DDT (Dichlorodiphenyltrichloroethane)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136755
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Sum DDT from MacDonald et al., 2000a which states that the probable effect concentration for Sum DDT is 62.9 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111506
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Deltamethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136740
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227643
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 5 samples exceed the water quality threshold for Deltamethrin.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/30/2007-12/16/2008.
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136826
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136930
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142282
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Deltamethrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2011-02-18 and 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142231
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Deltamethrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Deltamethrin is the USEPA Aquatic Life Benchmark of 0.0041 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-02-17 and 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136758
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136892
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2014-05-13 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111506, Deltamethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137082
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111510
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Demeton
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111510, Demeton
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142115
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Demeton, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111510, Demeton
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142129
 
Pollutant: Demeton
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Demeton, Total.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA National Recomm. Water Quality criteria, 4-day avg. is 0.1 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111473
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Diazinon
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6 additional lines of evidence are necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. Two of the 49 samples exceed the water quality threshold in water. Zero of the four samples exceed the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA 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 49 samples exceeded the water quality threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111473, Diazinon
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137104
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111473, Diazinon
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76130
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 27 samples exceed the criterion for Diazinon.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111473, Diazinon
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76131
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Diazinon.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected over the time period 6/29/2006-5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 111473, Diazinon
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142318
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 8 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111473, Diazinon
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137101
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111473, Diazinon
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142066
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Diazinon.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004).
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111474
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Dichlorvos
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of 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 not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 111474, Dichlorvos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142473
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 8 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2010-10-20 to 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111474, Dichlorvos
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142471
 
Pollutant: Dichlorvos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Dichlorvos. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Dichlorvos is the USEPA Aquatic Life Benchmark of 0.0058 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-01-12 to 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111475
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Dieldrin
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111475, Dieldrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137076
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111475, Dieldrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137167
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Dieldrin from MacDonald et al., 2000a which states that the probable effect concentration for Dieldrin is 61.8 ug/kg dw. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111500
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Dimethoate
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111500, Dimethoate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142474
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111500, Dimethoate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142432
 
Pollutant: Dimethoate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Dimethoate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Dimethoate is the USEPA Aquatic Life Benchmark of 0.5 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111476
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Endrin
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111476, Endrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137136
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111476, Endrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 136992
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Endrin from MacDonald et al., 2000a which states that the probable effect concentration for Endrin is 207 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111511
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137446
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137444
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2014-05-13 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142391
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227781
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227778
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-02-04
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227732
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137268
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137478
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111511, Esfenvalerate/Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142420
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111501
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Ethoprop
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111501, Ethoprop
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142366
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111501, Ethoprop
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142414
 
Pollutant: Ethoprop
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Ethoprop.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Ethoprop is the USEPA Aquatic Life Benchmark of 0.8 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111509
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fenpropathrin
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137481
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2012-10-16 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142721
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-02-17 and 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137469
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142691
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Fenpropathrin.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.06 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2011-02-18 and 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137461
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137379
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137515
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2013-01-31 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111509, Fenpropathrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137516
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111462
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fenvalerate
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111462, Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227816
 
Pollutant: Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenvalerate.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153)
Temporal Representation: The samples were collected between the dates of 2009-06-08 and 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111462, Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142818
 
Pollutant: Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenvalerate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2011-02-18 and 2011-02-18
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111462, Fenvalerate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142602
 
Pollutant: Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenvalerate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-02-17 and 2011-02-17
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111497
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fipronil
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111497, Fipronil
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137522
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111497, Fipronil
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137263
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111497, Fipronil
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137523
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111512
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fipronil Sulfide
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111512, Fipronil Sulfide
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137348
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111512, Fipronil Sulfide
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137297
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111512, Fipronil Sulfide
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137294
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111513
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fipronil Sulfone
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111513, Fipronil Sulfone
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137397
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111513, Fipronil Sulfone
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137362
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111513, Fipronil Sulfone
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137364
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111477
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fluoranthene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111477, Fluoranthene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137475
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for fluoranthene is 2,230 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111478
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Fluorene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111478, Fluorene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137525
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Fluorene from MacDonald et al., 2000a which states that the probable effect concentration for Fluorene is 536 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
132056
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Iron
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
Expected TMDL Completion Date: 2033
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132056, Iron
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233425
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River (Lower) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Iron.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan for the San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: National Recommended Water Quality Criteria Continuous Concentrations are intended protect aquatic organisms from chronic exposures (expressed as 4-day average concentration) in freshwater. The evaluation guideline for iron is 1,000 ug/L to protect warm freshwater habitat.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS)
Temporal Representation: The samples were collected between the dates of 2017-01-20 and 2017-05-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111479
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Lead
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of the 58 samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of four sediment samples exceed the water quality threshold for sediment; this sample size is not sufficient to determine beneficial use support with the power and confidence of the Listing Policy.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 58 samples exceeded the threshold, 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 met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143139
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143192
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76149
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego Dept. of Public Works data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76150
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected 6/3/2003 - 5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76152
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed County of San Diego NDPES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Lead.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Lead to protect aquatic life in freshwater. The dissolved Lead criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137562
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143392
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143313
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143433
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138059
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for lead in 128 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 142920
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111479, Lead
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143294
 
Pollutant: Lead
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111480
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111480, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137617
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Date for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111480, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137709
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for HCH, gamma- .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Lindane from MacDonald et al., 2000a which states that the probable effect concentration for Lindane is 4.99 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
128180
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Mercury
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 128180, Mercury
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138134
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury in 1.06 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 128180, Mercury
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 137940
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for mercury in 1.06 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111481
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111481, Methyl Parathion
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138656
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2015-04-24
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111481, Methyl Parathion
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138653
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111503
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Naled
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111503, Naled
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143129
 
Pollutant: Naled
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 5 samples exceeded the water quality threshold for Naled.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111503, Naled
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143402
 
Pollutant: Naled
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Naled.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Naled is the USEPA Aquatic Life Benchmark of 0.045 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111482
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Naphthalene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111482, Naphthalene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138401
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for naphthalene is 561 ug/kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111483
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Nickel
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Eleven lines of evidence are available in the administrative record to assess this pollutant. Zero of the 50 water samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of the four sediment samples exceed the water quality threshold for sediment; this sample size is not sufficient to determine beneficial use support with the power and confidence of the Listing Policy.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 50 samples exceeded the guideline, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76171
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed County of San Diego NDPES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 24 samples exceed the criterion for Nickel.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Nickel to protect aquatic life in freshwater. The dissolved Nickel criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76170
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego Dept. of Public Works data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Nickel.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138211
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel in 48.6 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143616
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143555
 
Pollutant: Nickel
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143465
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138275
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for nickel in 48.6 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143484
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143771
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143552
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111483, Nickel
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 143682
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
127742
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127742, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134756
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 6 samples collected by SWAMP Stream Pollution Trends for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Chironomus dilutus, for Survival, Hyalella azteca, for Survival, Chironomus dilutus, for Ash Free Dry Mass, Chironomus dilutus, for Growth (wt/surv indiv)
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 903SLRRBB )
Temporal Representation: The samples were collected between the dates of 2013-07-11 and 2018-05-03.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127742, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138178
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Total PAHs from MacDonald et al., 2000a which states that the probable effect concentration for Total PAHs is 22800 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127742, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 134760
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 2 samples collected by SWAMP Stream Pollution Trends for San Luis Rey River, Lower (west of Interstate 15) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day, at the same location with the same lab sample ID (if provided). The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca, for Growth (wt/surv indiv), Hyalella azteca, for Survival
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. 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.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 station. Monitoring site: ( 903SLSLR8 )
Temporal Representation: The samples were collected between the dates of 2011-10-27 and 2012-06-01.
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111489
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: PCBs (Polychlorinated biphenyls)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111489, PCBs (Polychlorinated biphenyls)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138623
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for PCBs in 676 ug/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111489, PCBs (Polychlorinated biphenyls)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138692
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for PCBs in 676 ug/Kg dry weight (MacDonald et al. 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111485
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: 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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111485, Parathion
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144838
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Parathion, Ethyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111485, Parathion
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144896
 
Pollutant: Parathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Parathion, Ethyl.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA recommended freshwater aquatic life ambient water quality chronic criteria for Parathion is 0.013 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
130308
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: 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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227800
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227751
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227836
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2007-11-30 to 2008-02-04
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138632
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2016-05-18
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145008
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 3 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138633
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144879
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The chronic concentration goal for Permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of Permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138580
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138484
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138482
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 130308, Permethrin
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138684
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111487
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Phenanthrene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111487, Phenanthrene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138974
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for phenanthrene is 1,170 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111502
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Phorate
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111502, Phorate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145758
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2011-01-12 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111502, Phorate
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145636
 
Pollutant: Phorate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Phorate.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Phorate is the USEPA Aquatic Life Benchmark of 0.21 ug/L for a invertebrate (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
 
DECISION ID
111490
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Pyrene
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111490, Pyrene
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138800
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for pyrene is 1,520 ug/kg dry weight (MacDonald et al 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2015-04-24 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111491
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Selenium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Two of the 70 samples exceed the water quality threshold.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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 70 samples exceeded the threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146522
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146490
 
Pollutant: Selenium
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146119
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146674
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146082
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146673
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146086
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146590
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146379
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146406
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 21182
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Three water samples were collected at San Luis Rey River station 903SLSLR2 May 2004, September 2004, March 2005, and April 2005. Two of three samples showed excessive selenium concentrations but one sample was "estimated" according to results in California's Surface Water Ambient Monitoring Program Report, 2007.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic
substances in concentrations that are toxic to, or
that produce detrimental physiological responses
in human, plant, animal, or aquatic life (RWQCB, 2007).
CTR Freshwater Chronic (CCC) 5 ug/L. (U.S. EPA, 2000).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Water samples were collected at San Luis Rey River station 903SLSLR2.
Temporal Representation: Samples were collected on May 2004, September 2004, March 2005, and April 2005.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 30918
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Fifteen water samples were collected at San Luis Rey River station. None of the 15 samples showed excessive selenium concentrations.
Data Reference: Urban Runoff Monitoring, Volume 1- Final Report To request a file review please contact the San Diego Regional Board receptionist. They may be reached by phone at (619) 516-1990, by email at rb9_records@waterboards.ca.gov, by fax at (619) 516-1994, or mail your request to: California Regional Water Quality Control Board Attention: File Review Request 2375 Northside Drive, Suite 100 San Diego, CA 92108 The ECM document handle is #2733059
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic
substances in concentrations that are toxic to, or
that produce detrimental physiological responses
in human, plant, animal, or aquatic life (RWQCB, 2007).
CTR Freshwater Chronic (CCC) 5 ug/L. (U.S. EPA, 2000).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Water samples were collected at San Luis Rey River under Benet Rd Bridge north of Highway 76.
Temporal Representation: Samples were collected on from November 2001 through February 2006.
Environmental Conditions:
QAPP Information: Quality control for this study was conducted in accordance with the Weston Solution's Quality Assurance Manual.
QAPP Information Reference(s): Weston Solutions, 2004. Quality Management Manual. March 2004 (Revised December 2009).
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76191
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 27 samples exceed the criterion for Selenium.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146557
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146404
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146143
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111491, Selenium
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146592
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
127532
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
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
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127532, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139361
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2012-06-01
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 127532, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139333
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for Total DDTs from MacDonald et al., 2000a which states that the probable effect concentration for Total DDTs is 572 ug/kg. (dw = Dry Weight)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
111494
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Turbidity
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
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Sixteen lines of evidence are available in the administrative record to assess this pollutant. Eleven of the 126 samples exceed the water quality threshold.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eleven of 126 samples exceeded the threshold 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147447
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 2 of 7 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147502
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Turbidity.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2011-06-11 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147610
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 26
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 26 samples exceeded the water quality threshold for Turbidity.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2011-04-16 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147568
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147731
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Turbidity.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2011-04-16 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233433
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for Santa Luis Rey River (Lower) to determine beneficial use support and results are as follows: 1 of 12 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2017-06-01
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147652
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147550
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147449
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147427
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 5 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR2)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2018-03-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147706
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147340
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147198
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR1)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2016-01-06
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147530
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 11 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-05
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147764
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 36
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 36 samples exceeded the water quality threshold for Turbidity.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2011-04-16 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111494, Turbidity
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147703
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111495
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Zinc
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary, and under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants in sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Zero of the 58 samples exceed the water quality threshold for the WARM/COLD beneficial use. Zero of four sediment samples exceed the water quality threshold for sediment; this sample size is not sufficient to determine beneficial use support with the power and confidence of the Listing Policy.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA 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. Zero of 58 samples exceeded the threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147834
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 148168
 
Pollutant: Zinc
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2013-05-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139432
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc in 459 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 148128
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147982
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139353
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for zinc in 459 mg/Kg dry weight (MacDonald et al. 2000a)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147937
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 148076
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-20 and 2015-05-06
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76219
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego Dept. of Public Works data for San Luis Rey River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River was collected at 1 monitoring site [ San Luis Rey River, lower - 903_SMC00153]
Temporal Representation: Data was collected on a single day 6/8/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76220
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 25
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: State Water Board staff assessed County of San Diego NDPES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 25 samples exceed the criterion for Zinc.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations for dissolved Zinc to protect aquatic life in freshwater. The dissolved Zinc criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/29/2001-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76218
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego DWM data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected 6/3/2003 - 5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 111495, Zinc
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 147848
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111486
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line of evidence is necessary to assess listing status. Sixteen line(s) of evidence are available in the administrative record to assess this pollutant. Sixteen of the 168 samples exceed the water quality threshold. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Sixteen of 168 samples exceeded the water quality threshold, 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145246
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2010-10-19 and 2015-05-05
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145244
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145414
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2)
Temporal Representation: The samples were collected between the dates of 2010-10-19 and 2013-05-01
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145381
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145502
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 24 samples exceeded the water quality threshold for pH.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145357
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR2)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2018-03-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145350
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145254
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 3 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLRRBB)
Temporal Representation: The samples were collected between the dates of 2014-05-13 and 2018-05-03
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145196
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145298
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145168
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145382
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 50
Number of Exceedances: 12
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 12 of 50 samples exceeded the water quality threshold for pH.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145327
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 17 samples exceeded the water quality threshold for pH.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145466
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR1)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2016-01-06
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145417
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 40
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 40 samples exceeded the water quality threshold for pH.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111486, pH
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 145095
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
111484
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2033
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Sixteen lines of evidence are available in the administrative record to assess this pollutant. Twelve of the 50 samples exceed the threshold.

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 CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Twelve of 50 samples exceed the threshold, 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.
 
Regional Board Decision 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.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144367
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR2)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2018-03-22
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144508
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Post-Construction BMP San Luis Rey Mitigation Bank data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLRR1)
Temporal Representation: The samples were collected between the dates of 2016-01-06 and 2016-01-06
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144509
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 4 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1)
Temporal Representation: The samples were collected between the dates of 2014-11-21 and 2015-05-05
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144628
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20214)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144753
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00665)
Temporal Representation: The samples were collected between the dates of 2011-07-27 and 2011-07-27
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144885
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-040)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144602
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903M20230)
Temporal Representation: The samples were collected between the dates of 2018-05-08 and 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144647
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 1 of 5 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-050)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-04-07
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144531
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLRRBB)
Temporal Representation: The samples were collected between the dates of 2017-05-02 and 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144530
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC00857)
Temporal Representation: The samples were collected between the dates of 2011-07-13 and 2011-07-13
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144768
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 3 of 9 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144516
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 4 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-030)
Temporal Representation: The samples were collected between the dates of 2017-02-04 and 2018-06-02
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144760
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01881)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144510
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC01689)
Temporal Representation: The samples were collected between the dates of 2012-07-05 and 2012-07-05
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144597
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SMC02905)
Temporal Representation: The samples were collected between the dates of 2013-07-09 and 2013-07-09
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111484, Oxygen, Dissolved
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 144544
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-010)
Temporal Representation: The samples were collected between the dates of 2016-08-20 and 2016-12-10
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
 
DECISION ID
111496
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Pyrethroids
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2033
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Under section 3.6, at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Twelve lines of evidence are available in the administrative record to assess this pollutant. Six of six samples exceed the water quality threshold in water. One of 15 samples exceed the water quality threshold in sediment, but this sample size is insufficient to determine beneficial use support with the statistical power and confidence of the Listing Policy.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of six samples exceed the water quality threshold in water, 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.
 
Regional Board Decision 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.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139183
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-1.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2014-11-25
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146148
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Pyrethroids. Although a total of 3 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-2).
Temporal Representation: Data for this waterbody was collected over the date range 2011-02-18 to 2013-02-09
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227984
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Stormwater Monitoring Coalition data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Metals, Nutrients, Inorganics, Pesticides and Toxicity from the Stormwater Monitoring Coalition Regional Monitoring of Southern California Coastal Watersheds, 2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903_SMC00153).
Temporal Representation: Date for this waterbody was collected over the date range 2009-06-08 to 2009-06-08
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the CRG Marine Laboratories and SMC Workplan.
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 227979
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 2 of the 2 samples exceeded the water quality threshold for Pyrethroids. Although a total of 3 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (903SLR-MLS).
Temporal Representation: Data for this waterbody was collected over the date range 2007-11-30 to 2008-12-16
Environmental Conditions:
QAPP Information: The Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233430
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River (Lower) to determine beneficial use support and the results are as follows: 3 of the 3 samples exceeded the water quality threshold for Pyrethroids. Although a total of 9 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-MLS).
Temporal Representation: Data for this waterbody was collected over the date range 2011-02-18 to 2017-05-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 233432
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River (Lower) to determine beneficial use support and the results are as follows: 0 of the 2 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-MLS.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-02-15
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138877
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20230.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138771
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 1 of the 2 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): SLR-TWAS-2.
Temporal Representation: Data for this waterbody were collected over the date range 2010-10-27 to 2013-01-31
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138841
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLSLR8.
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-27 to 2011-10-27
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 146113
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Region NPDES data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 5 samples were collected, 5 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in, human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site (SLR-TWAS-1).
Temporal Representation: Date for this waterbody was collected over the date range 2011-02-17 to 2015-03-02
Environmental Conditions:
QAPP Information: County of San Diego - Dept of Public Works. 2008. Quality Assurance Project Plan from Southern California Bight. ., Weston Solutions, Inc.. 2014. Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program., Wood. 2019. Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load., Weston Solutions, Inc.. 2019. Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring.
QAPP Information Reference(s): Quality Assurance Project Plan from Southern California Bight.
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency for NPDES Receiving Water Monitoring
QAPP Information Reference(s): Quality Assurance Project Plan for the County of San Diego's Inland Surface Water Monitoring Program
QAPP Information Reference(s): Quality Assurance Project Plan Equivalency Los Penasquitos Watershed Management Area Sediment Load Total Maximum Daily Load
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 139202
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Sediment, Toxicity data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903SLRRBB.
Temporal Representation: Data for this waterbody were collected over the date range 2013-07-11 to 2017-05-02
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 111496, Pyrethroids
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 138739
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SMC Regional Watershed Monitoring data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and the results are as follows: 0 of the 1 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 903M20214.
Temporal Representation: Data for this waterbody were collected over the date range 2018-05-08 to 2018-05-08
Environmental Conditions:
QAPP Information: Weston Solutions, Inc.. 2007. Regional Monitoring of Southern California's Coastal Watersheds., Weston Solutions, Inc.. 2019. Bioassessment Survey of the Stormwater Monitoring Coalition.
QAPP Information Reference(s): Regional Monitoring of Southern California's Coastal Watersheds
QAPP Information Reference(s): Bioassessment Survey of the Stormwater Monitoring Coalition
 
 
DECISION ID
70154
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Malathion
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 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. Two of the twenty-eight samples exceed the GUIDELINE.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List 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 twenty-eight samples exceeded the GUIDELINE 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 70154, Malathion
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76169
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Malathion.
Data Reference: Data for Metals, Nutrients, Inorganics, Organics, Pathogens, and Pesticides from the County of San Diego, 2003-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference: 2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 1 monitoring site [ San Luis Rey River at Highway 76 (Old Bonsall Bridge)]
Temporal Representation: Data was collected over the time period 6/29/2006-5/28/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8 was followed.
QAPP Information Reference(s): Quality Assurance Project Plan from the Truesdail Laboratories, Rev. 12, Enviromatrix Analytical and Dry Weather Monitoring Program Rev. 8.
 
Line of Evidence (LOE) for Decision ID 70154, Malathion
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76168
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 24
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed County of San Diego data for San Luis Rey River, Lower (west of Interstate 15) to determine beneficial use support and results are as follows: 2 of 24 samples exceed the criterion for Malathion.
Data Reference: Data for Various Pollutants from the County of San Diego Department of Public Works Watershed Protection Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments or biota at concentration(s) that adversely affect beneficial uses. Pesticides shall not be present at levels which will bioaccumulate in aquatic organisms to levels which are harmful to human health, wildlife or aquatic organisms (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The USEPA national ambient water quality criteria for freshwater aquatic life instantaneous maximum for malathion is 0.1 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for San Luis Rey River, Lower (west of Interstate 15) was collected at 2 monitoring sites [ San Luis Rey River - 903SLR-MLS, San Luis Rey River - 903SLR-TWAS-1]
Temporal Representation: Data was collected over the time period 11/8/2002-12/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan from Weston, the Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products were followed.
QAPP Information Reference(s): Quality Assurance Project Plan from Weston, The Regional Monitoring Workgroup Urban Runoff Monitoring Final Report Methods Sections and Statements of Work, and Weston Solutions Inc. Desk Reference for Quality Control Of Work Products.
 
 
DECISION ID
76476
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Sulfates
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: The decision has not changed from the previous listing cycle. No new data were assessed for the current listing cycle. Therefore, the previous conclusion remains unchanged, and is as follows:

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 one line of evidence is necessary to assess listing status.

One line of evidence are available in the administrative record to assess this pollutant. All four of the samples exceed the water quality objective.

According to Table 3.2 of the Listing Policy the minimum sample requirement is five.

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. All four samples exceeded the sulfate water quality objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of five samples is needed for application of table 3.2.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 76476, Sulfates
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 23500
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Eight water samples were collected at San Luis Rey River station 903SLSLR8 on May 2004, September 2004, March 2005, and April 2005. All four samples showed excessive sulfate concentrations according to results in California's Surface Water Ambient Monitoring Program Report, 2007.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The recommended secondary drinking water standard for sulfate is 250 mg/l (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Water samples were collected at San Luis Rey River station 903SLSLR8.
Temporal Representation: Samples were collected on May 2004, September 2004, March 2005, and April 2005.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
70155
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of the 42 samples exceed the beneficial use guidelines.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of 42 samples exceeded the guideline 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.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 70155, Temperature, water
Region 9     
San Luis Rey River, Lower (west of Interstate 15)
 
LOE ID: 76192
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 42
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One of the 42 samples exceeded the evaluation guideline for temperature in this water body.
Data Reference: Data for Trash, Nutrients, and Pathogens in Region 9, 2007-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5°F above the natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129). Since there is no evaluation guideline for assessing temperature for the warm freshwater aquatic life beneficial use, this line of evidence will not be used for Listing Decisions in the 2012 Integrated Report and will be retired for said Listing cycle.
Guideline Reference: Fish introductions in CA: History and impact on native fishes. Davis, CA: University of CA, Davis
 
Spatial Representation: Samples were collected at the following stations: SLR-010-Pacific Coast Highway Bridge SLR-020-Shearer Crossing SLR-030-Douglas Ave Bridge SLR-040-Near Mission Ave where Hwy 76 crosses SLR SLR-050-Old Hwy 395 bridge W side of Interstate 15
Temporal Representation: Samples were collected between January, 2009 and July, 2010.
Environmental Conditions:
QAPP Information: San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan Prepared by: Clay Clifton (San Diego Coastkeeper, Local Project Sponsor Manager), Bob Stafford (San Diego Stream Team), Dr. Rick Gersberg (San Diego State University), Bryan Bjorndal (Assure Controls, Inc.), and Morgan Justice-Black (I Love A Clean San Diego).
QAPP Information Reference(s):