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

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Redhawk Channel
Water Body ID: CAR9025100020080904171327
Water Body Type: River & Stream
 
DECISION ID
127523
Region 9     
Redhawk Channel
 
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.

Two lines of evidence are available in the administrative record to assess pollutant. Seven of the eight 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 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. Seven of the eight samples exceed the water quality 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 127523, Nitrogen
Region 9     
Redhawk Channel
 
LOE ID: 7473
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 6
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Six out of seven samples collected exceed the evaluation guideline of 1 mg/L according to the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from July 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
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 phosphorus, 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 Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to five samples were collected per monitoring year. Samples collected in July 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low 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 127523, Nitrogen
Region 9     
Redhawk Channel
 
LOE ID: 144058
 
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 SWAMP RWB9 Monitoring data for Redhawk Channel 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, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
113387
Region 9     
Redhawk Channel
 
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.

Two lines of evidence are available in the administrative record to assess pollutant. Eight of the eight 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. Eight of eight samples exceeded 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 113387, Phosphorus
Region 9     
Redhawk Channel
 
LOE ID: 7474
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All seven samples collected exceed the evaluation guideline according to the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from July 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
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).
Water Quality Control Plan for the San Diego Basin has a 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 Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to five samples were collected per monitoring year. Samples collected in July 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low 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 113387, Phosphorus
Region 9     
Redhawk Channel
 
LOE ID: 145704
 
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 SWAMP RWB9 Monitoring data for Redhawk Channel 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, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
113388
Region 9     
Redhawk Channel
 
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: 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 4.2 of the Listing Policy. Under this section 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. Seven of the 10 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. Seven of 10 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 113388, Total Dissolved Solids
Region 9     
Redhawk Channel
 
LOE ID: 7472
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 6
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Six out of nine samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, inland surface waters designated as domestic or municipal supply, shall not contain concentrations of iron in excess of the secondary maximum contaminant level 0.3 mg/L (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Two to four samples were collected per monitoring year. Samples were collected from October 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low 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 113388, Total Dissolved Solids
Region 9     
Redhawk Channel
 
LOE ID: 147356
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB9 Monitoring data for Redhawk Channel to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
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 113388, Total Dissolved Solids
Region 9     
Redhawk Channel
 
LOE ID: 147283
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 SWAMP RWB9 Monitoring data for Redhawk Channel to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
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 113388, Total Dissolved Solids
Region 9     
Redhawk Channel
 
LOE ID: 147007
 
Pollutant: Total Dissolved Solids
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 SWAMP RWB9 Monitoring data for Redhawk Channel to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Total Dissolved Solids.
Data Reference: Field, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
126456
Region 9     
Redhawk Channel
 
Pollutant: Benthic Community Effects
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. No additional lines of evidence associating the Benthic Community Effects decision with pollutants are available.

One line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/are available in the administrative record to assess this indicator. Two of two benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. Information submitted to the San Diego Water Board indicates this stream was sampled under a 100 percent unexempted non-stormwater discharge, and that the stream is no longer flowing due to its elimination.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this waterbody segment 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. Two of two benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. The available information is insufficient to determine whether the waterbody/pollutant combination should be placed on the 303(d) List of impaired waters at this time as additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants are not available and information indicates the stream is ephemeral.
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:
 
 
Line of Evidence (LOE) for Decision ID 126456, Benthic Community Effects
Region 9     
Redhawk Channel
 
LOE ID: 215715
 
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 902RDH768 to determine beneficial use support and the results are as follows: 2 of 2 samples exceeded the threshold. CSCI scores were from 0.3697 to 0.4632 .
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 902RDH768
Temporal Representation: Samples were collected from 5/22/2013 to 5/22/2014.
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.
 
 
DECISION ID
113386
Region 9     
Redhawk Channel
 
Pollutant: Oxygen, Dissolved
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 113386, Oxygen, Dissolved
Region 9     
Redhawk Channel
 
LOE ID: 75521
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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: Zero of 4 samples exceeded the objective.
Data Reference: Data for Various Pollutants in Riverside County, 2007-2009.
 
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 designated MAR or WARM beneficial uses. The annual mean dissolved oxygen concentration shall not be less than 7 mg/l more than 10% of the time.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the Redhawk Channel Station.
Temporal Representation: Samples were collected four times between 2007 and 2009.
Environmental Conditions:
QAPP Information: NPDES quality assurance.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 113386, Oxygen, Dissolved
Region 9     
Redhawk Channel
 
LOE ID: 144679
 
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 RWB9 Monitoring data for Redhawk Channel 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, Tissue, Water 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
127426
Region 9     
Redhawk Channel
 
Pollutant: Specific Conductivity
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 127426, Specific Conductivity
Region 9     
Redhawk Channel
 
LOE ID: 146962
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB9 Monitoring data for Redhawk Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
Data Reference: Field, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the maximum contaminant levels specified in Table 64449-A of section 64449 of Title 22 of the California Code of Regulations (Secondary Maximum Contaminant Levels, Consumer Acceptance Limits) which is incorporated by reference into this plan. (Water Quality Control Plan, San Diego Basin). The California Secondary MCL for specific conductance is 900 uS/cm (Title 22 California Code of Regulations).
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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
113389
Region 9     
Redhawk Channel
 
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: 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 113389, Turbidity
Region 9     
Redhawk Channel
 
LOE ID: 147745
 
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 SWAMP RWB9 Monitoring data for Redhawk Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: 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 (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
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 113389, Turbidity
Region 9     
Redhawk Channel
 
LOE ID: 147475
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB9 Monitoring data for Redhawk Channel 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, Sediment, Tissue, Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Secondary California Maximum Contaminant Level for Turbidity is 5 NTU (Title 22 of the California Code of Regulations).
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (902LTRED1)
Temporal Representation: The samples were collected between the dates of 2012-03-16 and 2012-03-16
Environmental Conditions:
QAPP Information: SWAMP QAPrP 2008, Nagoda and Busse, 2013. Quality Assurance Project Plan for Screening of Cyanotoxins in Lakes/Reservoirs and Coastal Wetlands in the San Diego Region, SWAMP QAPrP 2017
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
76873
Region 9     
Redhawk Channel
 
Pollutant: Indicator Bacteria
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)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2025
Impairment from Pollutant or Pollution: Pollution
 
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.

Three lines of evidence are available in the administrative record to assess this pollutant. With the latest data, 7 of 9 single samples exceed the water quality objective for E. Coli. of 235/100ml and for fecal coliform of 400/100ml for the protection of REC-1.

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. With the latest data, 7 of 9 single samples exceed the water quality objective for E. Coli. of 235/100ml and for fecal coliform of 400/100ml for the protection of REC-1 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 76873, Indicator Bacteria
Region 9     
Redhawk Channel
 
LOE ID: 72787
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the two samples exceeded the E. coli objective.
Data Reference: Data for Various Pollutants in Riverside County, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The E.Coli concentration shall not exceed more than 235/100 ml. 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: The samples were collected at Redhawk Channel.
Temporal Representation: Samples were collected between November 2008 and June 2009.
Environmental Conditions:
QAPP Information: No QAPP was submitted. Sampling was done by municipalities in Riverside County pursuant to the Riverside County Municipal Stormwater Permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76873, Indicator Bacteria
Region 9     
Redhawk Channel
 
LOE ID: 7466
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All seven samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The maximum E. coli level for moderately or lightly used areas is 406 colonies per 100 ml (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to four samples were collected per monitoring year. Samples were collected from October 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, two dry events were monitored in the 2004-2005 monitoring year and one dry event in the 2005-2006 monitoring year due to low 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 76873, Indicator Bacteria
Region 9     
Redhawk Channel
 
LOE ID: 7465
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All seven samples collected exceed the water quality objective according to the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through February 2006. .
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
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 per 100 ml (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to four samples were collected per monitoring year. Samples were collected from October 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, two dry events were monitored in the 2004-2005 monitoring year and one dry event in the 2005-2006 monitoring year due to low 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 76873, Indicator Bacteria
Region 9     
Redhawk Channel
 
LOE ID: 72786
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the two samples exceeded the fecal coliform objective.
Data Reference: Data for Various Pollutants in Riverside County, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Fecal Coliform concentration shall not exceed more than 400/100 ml. 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: The samples were collected at Redhawk Channel.
Temporal Representation: Samples were collected between November 2008 and June 2009.
Environmental Conditions:
QAPP Information: No QAPP was submitted. Sampling was done by municipalities in Riverside County pursuant to the Riverside County Municipal Stormwater Permit.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76873, Indicator Bacteria
Region 9     
Redhawk Channel
 
LOE ID: 72785
 
Pollutant: Total Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Zero of the two samples exceeded the total coliform objective.
Data Reference: Data for Various Pollutants in Riverside County, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. Basin Plan for the San Diego Basin.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The Total Coliform concentration shall not exceed more than 10000/100 ml. Guidance for Fresh Water Beaches (CDPH).
Guideline Reference: Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.
 
Spatial Representation: The samples were collected at Redhawk Channel.
Temporal Representation: Samples were collected between November 2008 and June 2009.
Environmental Conditions:
QAPP Information: No QAPP was submitted. Sampling was done by municipalities in Riverside County pursuant to the Riverside County Municipal Stormwater Permit.
QAPP Information Reference(s):
 
 
DECISION ID
83739
Region 9     
Redhawk Channel
 
Pollutant: pH
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. Four of the Four samples exceed the Water Quality Objective for pH.

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. Four of Four samples exceeded the Water Quality Objective for pH for and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples is needed to determine if a beneficial use is fully supported using 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: 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 83739, pH
Region 9     
Redhawk Channel
 
LOE ID: 75522
 
Pollutant: pH
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: Four of 4 samples exceeded the objective.
Data Reference: Data for Various Pollutants in Riverside County, 2007-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of all inland surface waters shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the Red Hawk Channel station.
Temporal Representation: Samples were collected approximately once a year from 2007 to 2009.
Environmental Conditions:
QAPP Information: NPDES quality assurance.
QAPP Information Reference(s):
 
 
DECISION ID
76333
Region 9     
Redhawk Channel
 
Pollutant: Chlorpyrifos
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
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 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Seven of eight of the samples exceed the Basin Plan water quality objective for chlorpyrifos.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Seven of eight of the samples exceed the Basin Plan water quality objective for chlorpyrifos, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
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 76333, Chlorpyrifos
Region 9     
Redhawk Channel
 
LOE ID: 7467
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 7
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Four out of four wet weather samples collected exceed the water quality objective of 0.025 ug/L. Three out of four dry weather samples exceed 0.014 ug/L according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from July 2004 through February 2006.
Data Reference: Water Quality Control Plan for the San Diego Basin
 
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 (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The 4-day average concentration of chlorpyrifos in freshwater is 0.014 ug/L. The 1-hour average concentration of chlorpyrifos in freshwater is 0.025 ug/L according to Siepmann and Finlayson, 2000; Finlayson, 2004.
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to five samples were collected per monitoring year. Samples were collected from July 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low flow.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
 
DECISION ID
77015
Region 9     
Redhawk Channel
 
Pollutant: Copper
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
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 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Two of eight of the samples exceed the California Toxic Rule water quality objective for copper.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of eight of the samples exceed the California Toxic Rule water quality objective for copper, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
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 77015, Copper
Region 9     
Redhawk Channel
 
LOE ID: 7468
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Two out of four wet weather samples collected exceed the water quality objective for the 1-hour average concentration of copper. None of four dry weather samples collected exceeds the water quality objective for the 4-day average concentration of copper according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from July 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the CTR, the dissolved copper chronic criterion is 3.1 ppb and the acute criterion is 4.8 ppb, but these criteria may vary depending upon hardness of the sample (U.S. EPA, 2000).
Objective/Criterion Reference: Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic Pollutants for the State of California; Rule. 40 CFR Part 131. U.S. Environmental Protection Agency, Region IX, Water Division, San Francisco, CA
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to five samples were collected per monitoring year. Samples were collected from July 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low flow.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
 
DECISION ID
76850
Region 9     
Redhawk Channel
 
Pollutant: Diazinon
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
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 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One lines of evidence is available in the administrative record to assess this pollutant. Two of eight of the samples exceed the Basin Plan water quality objective for Dianzinon.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of eight of the samples exceed the Basin Plan water quality objective for Dianzinon, 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: 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 76850, Diazinon
Region 9     
Redhawk Channel
 
LOE ID: 7469
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Two out of eight samples collected exceed the water quality objective; these two exceedances occurred within a one year period according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from July 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in the water column, sediments of 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 organism (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The one-hour average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (acute criterion) and the four-day average concentration of diazinon should not exceed 0.17 µg/L more than once every three years on the average (chronic criterion). (U.S. EPA, 2006)
Guideline Reference: Fact Sheet: Final Recommended Aquatic Life Ambient Water Quality Criteria for Diazinon
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Three to five samples were collected per monitoring year. Samples were collected from July 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low flow.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
 
DECISION ID
76702
Region 9     
Redhawk Channel
 
Pollutant: Iron
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown | Natural Sources
Expected TMDL Completion Date: 2019
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 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. Five of six of the samples exceed the Basin Plan water quality objective for iron.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of six of the samples exceed the Basin Plan water quality objective for iron, 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: 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 76702, Iron
Region 9     
Redhawk Channel
 
LOE ID: 7470
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 5
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Five out of six samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006, Samples were collected from October 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, inland surface waters designated as domestic or municipal supply, shall not contain concentrations of iron in excess of the secondary maximum contaminant level 0.3 mg/L (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Two to four samples were collected per monitoring year. Samples were collected from October 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low flow.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):
 
 
DECISION ID
76851
Region 9     
Redhawk Channel
 
Pollutant: Manganese
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2021
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 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. Six of six of the samples exceed the Basin Plan water quality objective for manganese.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six of six of the samples exceed the Basin Plan water quality objective for manganese, 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: 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 76851, Manganese
Region 9     
Redhawk Channel
 
LOE ID: 7471
 
Pollutant: Manganese
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All six samples collected exceed the water quality objective according to results in the Riverside County Flood Control and Water Conservation District annual progress report from 2005 and 2006. Samples were collected from October 2004 through February 2006.
Data Reference: Watershed Annual Progress Report 2004 to 2005 and 2005 to 2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, inland surface waters designated as domestic or municipal supply shall not contain concentrations of manganese in excess of the secondary maximum contaminant level 0.05 mg/L (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Redhawk Channel downstream of Overland Dr. Lat/long: 33°28¿34.6¿ N/117°05¿40.8¿ W.
Temporal Representation: Two to four samples were collected per monitoring year. Samples were collected from October 2004 through February 2006.
Environmental Conditions: One sample represents the first storm event of each monitoring year that produces sufficient flow to collect a composite sample. In addition, another sample is collected during the monitoring year to represent a wet weather event. Two dry sampling events are also required each monitoring year; however, three dry events were monitored in the 2004-2005 monitoring year and only one dry event in the 2005-2006 monitoring year due to low flow.
QAPP Information: QA/QC conducted according to Federal Regulations under requirements of a NPDES permit.
QAPP Information Reference(s):