Draft California 2018 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name: Sheep Creek
Water Body ID: CAR6282000020070828155444
Water Body Type: River & Stream
 
DECISION ID
76461
Region 6     
Sheep Creek
 
Pollutant: Nitrogen, Nitrate
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)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2031
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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, one evaluating data for the COLD beneficial use and one evaluating data for the MUN beneficial use, are available in the administrative record to assess pollutant. 0 of 12 samples exceed the objective for the MUN beneficial use; 3 of 5 samples exceed the objective for the COLD beneficial use.

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. 3 of 5 samples exceeded the objective for the COLD beneficial use 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 76461, Nitrogen, Nitrate
Region 6     
Sheep Creek
 
LOE ID: 7983
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program between 2001 and 2005. Twelve samples each were analyzed for nitrite and nitrite plus nitrate, both expressed "as nitrogen." Nitrate was calculated by subtraction. Calculated "nitrate as nitrogen" concentrations included four estimated or below detection level values. The remaining 8 samples ranged from 0.046 to 0.24 mg/L. Expressed "as nitrate", these samples ranged from 0.207 to 1.08 mg/L. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for nitrate is 45 mg/L expressed "as nitrate," equivalent 10 mg/L expressed "as nitrogen."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples each (2 to 4 per year) were collected for nitrite and nitrite plus nitrate between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76461, Nitrogen, Nitrate
Region 6     
Sheep Creek
 
LOE ID: 7971
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 3
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program between 2001 and 2005. Twelve samples each were analyzed for nitrite and nitrite plus nitrate, both expressed "as nitrogen." Nitrate was calculated by subtraction. Calculated "nitrate as nitrogen" concentrations included four estimated or below detection level values. The remaining 8 samples ranged from 0.046 to 0.24 mg/L. Expressed "as nitrate", these samples ranged from 0.207 to 1.08 mg/L. Two of five calculated annual averages were estimates due to estimated and below detection level data. The remaining averages ranged from 0.458 to 0.893 mg/L nitrate "as nitrate." The site-specific objective was violated in 3 of 5 years.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site-specific objective from Lahontan Basin Plan Table 3-21 includes an annual average nitrate concentration of 0.3 mg/L and a 90th percentile value of 1.3 mg/L, both expressed "as nitrate."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples each (2 to 4 per year) were collected for nitrite and nitrite plus nitrate between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
77368
Region 6     
Sheep Creek
 
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)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2031
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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, two which assess the available data for the COLD beneficial use and one which assesses the available data for the MUN beneficial use, are available in the administrative record to assess this pollutant. 11 of 11 samples exceed the objectives for the COLD beneficial use, 0 of 12 samples exceed the objectives for the MUN beneficial use.

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. 11 of 11 samples exceeded the objective for the COLD beneficial use 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 77368, Total Dissolved Solids
Region 6     
Sheep Creek
 
LOE ID: 96626
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan Water Board staff conducting routine Surface Water Ambient Monitoring Program (SWAMP) sampling. Data were collected between November 2011 and April 2015. Concentrations in the raw data ranged from 83 to 121 mg/L. Six annual averages were computed, all of which exceeded the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for total dissolved solids in Sheep Creek, as referenced in the Lahontan Basin Plan table 3-21, is an annual average not to exceed 56 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 628SHP001, which is located below the Scout Camp off of Deep Creek Camp Road.
Temporal Representation: Data were collected beginning in November 2010, and were collected three times per calendar year in the spring, summer and fall in 2011 and 2012. One field visit was made each year in the spring of 2013, 2014 and 2015.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
Line of Evidence (LOE) for Decision ID 77368, Total Dissolved Solids
Region 6     
Sheep Creek
 
LOE ID: 5304
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Total Dissolved Solids (TDS) under the Region 6 SWAMP program between 2001 and 2005. TDS concentrations in 12 quarterly samples ranged from 101 to 196 mg/L. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for Total Dissolved Solids is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77368, Total Dissolved Solids
Region 6     
Sheep Creek
 
LOE ID: 5303
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Total Dissolved Solids (TDS) under the Region 6 SWAMP program between 2001 and 2005. Concentrations of TDS in 12 quarterly samples ranged from 101 to 196 mg/L. The annual average objective was violated in 5 of 5 years.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site-specific objective from Lahontan Basin Plan Table 3-21 includes an annual average of 56 mg/L and a 90th percentile value of 72 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
70854
Region 6     
Sheep Creek
 
Pollutant: Alkalinity as CaCO3
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: 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.

Three lines of evidence, one which assesses the available Acid Neutralizing Capability data and two which assess the available Alkalinity as CaCO3 data, are available in the administrative record to assess this pollutant. Acid Neutralizing Capacity (ANC) is equivalent to alkalinity, and the USEPA "Gold Book" criterion for alkalinity states that it should be greater than 20 mg/L CaCO3 unless natural alkalinity is lower. 0 of 12 samples exceed the water quality objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 12 samples exceed the objective 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 are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 70854, Alkalinity as CaCO3
Region 6     
Sheep Creek
 
LOE ID: 98561
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold 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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The National Recommended Water Quality Criteria for Alkalinity as CaCO3 for the protection of freshwater aquatic life is not less than 20000 ug/L. (National Recommended Water Quality Criteria 2016)
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-04-19 and 2011-06-22
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 70854, Alkalinity as CaCO3
Region 6     
Sheep Creek
 
LOE ID: 7961
 
Pollutant: Acid Neutralizing Capacity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program. One sample collected on March 20, 2003 was analyzed for ANC. The result was 7.8 mg/L CaCO3.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There are no California or federal standards or criteria for acid neutralizing capacity (ANC) per se. However, ANC is equivalent to alkalinity, and the U.S. Environmental Protection Agency "Gold Book" recommends alkalinity greater than 20 mg/L CaCO3 unless natural alkalinity is lower.
Objective/Criterion Reference: Quality Criteria for Water 1986. United States Environmental Protection Agency. Office of Water. Regulations and Standards. Washington D.C. EPA 440/5-86-001.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: One sample was collected on March 20, 2003.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70854, Alkalinity as CaCO3
Region 6     
Sheep Creek
 
LOE ID: 97068
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold 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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality standard for Alkalinity as CaCO3.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The National Recommended Water Quality Criteria for Alkalinity as CaCO3 for the protection of freshwater aquatic life is not less than 20000 ug/L. (National Recommended Water Quality Criteria 2016)
Objective/Criterion Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
102256
Region 6     
Sheep Creek
 
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 Staff 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 which assess the available data for the COLD and WARM beneficial uses respectively, are available in the administrative record to assess this pollutant. 0 of 1 samples in each beneficial use assessment exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 1 samples in each beneficial use assessment exceeded the objective 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 16 samples per beneficial use assessed are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 102256, Ammonia
Region 6     
Sheep Creek
 
LOE ID: 98547
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold 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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: 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(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-04-19 and 2011-04-19
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102256, Ammonia
Region 6     
Sheep Creek
 
LOE ID: 98548
 
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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: 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(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-04-19 and 2011-04-19
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
71444
Region 6     
Sheep Creek
 
Pollutant: Boron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: 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.

Three lines of evidence, two which assess the available data for the COLD beneficial use and one which assesses the available data for the MUN beneficial use, are available in the administrative record to assess this pollutant. 1 of 11 samples exceed the objectives for the COLD beneficial use and 0 of 9 samples exceed the objectives for the MUN beneficial use.

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 satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region.
3. 1 of 11 samples exceed the objectives for the COLD beneficial use and 0 of 9 samples exceed the objectives for the MUN beneficial use 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 16 samples are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 71444, Boron
Region 6     
Sheep Creek
 
LOE ID: 96622
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan Water Board staff conducting routine Surface Water Ambient Monitoring Program (SWAMP) sampling. Data were collected between November 2011 and April 2015. Concentrations in the raw data ranged from 0.0027 to 0.095 mg/L. Six annual averages were computed, one of which exceeded the site specific objective in 2015. This exceedance was based on only one data point however.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for Boron in Sheep Creek, as referenced in the Lahontan Basin Plan table 3-21, is an annual average not to exceed 0.01 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 628SHP001, which is located below the Scout Camp off of Deep Creek Camp Road.
Temporal Representation: Data were collected beginning in November 2010, and were collected three times per calendar year in the spring, summer and fall in 2011 and 2012. One field visit was made each year in the spring of 2013, 2014 and 2015.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
Line of Evidence (LOE) for Decision ID 71444, Boron
Region 6     
Sheep Creek
 
LOE ID: 5292
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled boron under the Region 6 SWAMP program between 2001 and 2005. Boron concentrations in 7 of 9 samples were estimated or below detection level values. Concentrations in the remaining samples were 9.9 and 24 ug/L. The annual average objective was not exceeded.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site-specific objective from Lahontan Basin Plan Table 3-21 includes an annual average boron concentration of 0.01 mg/L (or 10 ug/L), and a 90th percentile value of 0.02 mg/L (or 20 ug/L).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Nine samples were collected between 2001 and 2005. One sample was collected in 2001, and samples were collected quarterly between December 2002 and July 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 71444, Boron
Region 6     
Sheep Creek
 
LOE ID: 7960
 
Pollutant: Boron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled boron under the Region 6 SWAMP program between 2001 and 2005. Boron concentrations in 7 of 9 samples were estimated or below detection level values. Concentrations in the remaining samples were 9.9 and 24 ug/L. The criterion was not exceeded.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California State Notification Level criterion is 1000 ug/L.
Objective/Criterion Reference: Compilation of Water Quality Goals
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Nine samples were collected between 2001 and 2005. One sample was collected in 2001, and samples were collected quarterly between December 2002 and July 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
71276
Region 6     
Sheep Creek
 
Pollutant: Chloride
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: 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.

Three lines of evidence, two which assess the available data for the COLD beneficial use and one which assess the data for the MUN beneficial use, are available in the administrative record to assess this pollutant. 4 of 11 samples exceed the objective for the COLD beneficial use and 0 of 12 samples exceed the objective for the MUN beneficial use.

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 satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region.
3. 4 of 11 samples exceed the objective for the COLD beneficial use and 0 of 12 samples exceed the objective for the MUN beneficial use and these sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples per beneficial use assessed are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 71276, Chloride
Region 6     
Sheep Creek
 
LOE ID: 5297
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled chloride under the Region 6 SWAMP program. Chloride concentrations in 12 quarterly samples ranged from 5.08 to 27.2 mg/L. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for chloride is 250 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 71276, Chloride
Region 6     
Sheep Creek
 
LOE ID: 96623
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan Water Board staff conducting routine Surface Water Ambient Monitoring Program (SWAMP) sampling. Data were collected between November 2011 and April 2015. Concentrations in the raw data ranged from 3.71 to 5.55 mg/L. Six annual averages were computed, none of which exceeded the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for chloride in Sheep Creek, as referenced in the Lahontan Basin Plan table 3-21, is an annual average not to exceed 6.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 628SHP001, which is located below the Scout Camp off of Deep Creek Camp Road.
Temporal Representation: Data were collected beginning in November 2010, and were collected three times per calendar year in the spring, summer and fall in 2011 and 2012. One field visit was made each year in the spring of 2013, 2014 and 2015.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
Line of Evidence (LOE) for Decision ID 71276, Chloride
Region 6     
Sheep Creek
 
LOE ID: 5296
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled chloride under the Region 6 SWAMP program between 2001 and 2005. Chloride concentrations in 12 quarterly samples ranged from 5.08 to 27.2 mg/L. The annual average objective was violated in 4 of 5 years.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective from Lahontan Basin Plan Table 3-21 includes an annual average chloride concentration of 6.0 mg/L and a 90th percentile value of 7.8 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
70544
Region 6     
Sheep Creek
 
Pollutant: Fluoride
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: 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.

Three lines of evidence, two which assess the available data for the MUN beneficial use and one which assesses the available data for the COLD beneficial use, are available in the administrative record to assess this pollutant. 2 of 15 samples exceed the objective for the MUN beneficial use and 0 of 5 samples exceed the objective for the COLD beneficial use.

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 satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region.
3. 2 of 15 samples exceed the objective for the MUN beneficial use; 0 of 5 samples exceeded the objective for the COLD beneficial use. These sample sizes do 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 70544, Fluoride
Region 6     
Sheep Creek
 
LOE ID: 96624
 
Pollutant: Fluoride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan Water Board staff conducting routine Surface Water Ambient Monitoring Program (SWAMP) sampling. Data were collected between November 2011 and April 2015. Concentrations in the raw data ranged from non-detect to 0.182 mg/L. Six annual averages were computed, two of which exceeded the site specific objective in 2014 and 2015 (one sample collected per year: 0.182 mg/L in 2014 and 0.134 mg/L in 2015)
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for fluoride in Sheep Creek, as referenced in the Lahontan Basin Plan table 3-21, is an annual average not to exceed 0.13 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 628SHP001, which is located below the Scout Camp off of Deep Creek Camp Road.
Temporal Representation: Data were collected beginning in November 2010, and were collected three times per calendar year in the spring, summer and fall in 2011 and 2012. One field visit was made each year in the spring of 2013, 2014 and 2015.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
Line of Evidence (LOE) for Decision ID 70544, Fluoride
Region 6     
Sheep Creek
 
LOE ID: 5299
 
Pollutant: Fluoride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled fluoride under the Region 6 SWAMP program between 2001 and 2005. Fluoride concentrations in 9 quarterly samples were all estimated or below detection level values. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for fluoride is 2 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Nine quarterly samples were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70544, Fluoride
Region 6     
Sheep Creek
 
LOE ID: 5298
 
Pollutant: Fluoride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled fluoride under the Region 6 SWAMP program between 2001 and 2005. Fluoride concentrations in 9 quarterly samples were all estimated or below detection level values. The annual average objective was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective from Lahontan Basin Plan Table 3-21 includes an annual average fluoride concentration of 0.13 mg/L and a 90th percentile value of 0.22 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Nine quarterly samples were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
102254
Region 6     
Sheep Creek
 
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
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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.

Three lines of evidence which assess the available data for the COLD, WARM and MUN beneficial uses are available in the administrative record to assess this pollutant. 0 of 1 samples in each beneficial use assessment exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 1 samples in each beneficial use assessment exceeded the objective 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 16 samples per beneficial use assessed are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 102254, Iron
Region 6     
Sheep Creek
 
LOE ID: 98222
 
Pollutant: Iron
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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Iron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: 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, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: The Red Book states that based on field observations principally, a criterion of 1.0 mg/L iron for freshwater aquatic life is believed to be adequately protective.
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2010-11-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102254, Iron
Region 6     
Sheep Creek
 
LOE ID: 97054
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Iron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Lahontan Region?s Objective for Municipal and Domestic Supply uses of inland surface waters states that waters designated as MUN shall not contain concentrations of chemical constituents in excess of the maximum contaminant level (MCL) or secondary maximum contaminant level (SMCL). This is based upon drinking water standards specified in the following provisions of Title 22 of the California Code of Regulations which are incorporated by reference into the Water Quality Control Plan: Table 64431-A of Section 64431 (Inorganic Chemicals), Table 64431-B of Section 64431 (Fluoride), Table 64444-A of Section 64444 (Organic Chemicals), Table 64449-A of Section 64449 (Secondary Maximum Contaminant Levels-Ranges). The maximum contaminant level listed in Table 64449-A for Iron is 0.3 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2010-11-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102254, Iron
Region 6     
Sheep Creek
 
LOE ID: 98220
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold 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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Iron.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: 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, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: The Red Book states that based on field observations principally, a criterion of 1.0 mg/L iron for freshwater aquatic life is believed to be adequately protective.
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2010-11-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
71277
Region 6     
Sheep Creek
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. 0 of 22 samples exceed the water quality objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 22 samples exceed the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 71277, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Sheep Creek
 
LOE ID: 98542
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality standard for Nitrate + Nitrite as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Water Quality Control Plan, Lahontan Region is 10.0 mg/L (Water Quality Control Plan, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2012-04-05 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71277, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Sheep Creek
 
LOE ID: 97111
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Nitrate + Nitrite as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Water Quality Control Plan, Lahontan Region is 10.0 mg/L (Water Quality Control Plan, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2010-11-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 71277, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Sheep Creek
 
LOE ID: 7964
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled nitrite plus nitrate under the Region 6 SWAMP program between 2001 and 2005. Of 12 quarterly samples, one was below the detection level and two were estimated values. Nitrite plus nitrate concentrations in the remaining samples ranged from 0.046 to 0.213 mg/L. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for nitrite plus nitrate (expressed "as nitrogen") is 10 is mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 71277, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Sheep Creek
 
LOE ID: 98541
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality standard for Nitrate + Nitrite as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Water Quality Control Plan, Lahontan Region is 10.0 mg/L (Water Quality Control Plan, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-06-22 and 2011-11-02
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
76416
Region 6     
Sheep Creek
 
Pollutant: Nitrogen
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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 eleven samples exceed the site specific objective for Nitrogen for Deep Creek that applies to Sheep Creek due to the tributary rule, however the line of evidence from 2010 is based on estimated and summed data for total nitrogen that is not necessary equivalent to data in the more recent line of evidence. Consequently while the data suggests there may be impairment due to nitrogen, it is not sufficient to place it on the CWA section 303(d) List.

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. Two of eleven samples exceed the objective and while this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy, as stated above there is some question regarding the data in the previous line of evidence so this waterbody is recommended to be placed in Category 3. .
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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 76416, Nitrogen
Region 6     
Sheep Creek
 
LOE ID: 8063
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program between 2001 and 2005. Twelve quarterly samples each were collected for total Kjeldahl nitrogen and nitrite plus nitrate. Total nitrogen was calculated from these samples. Due to estimated and below detection level values in the component samples, 6 of 12 total nitrogen values were estimates. The remainder of the calculated total nitrogen concentrations ranged from 0.196 to 0.528 mg/L. Three of five annual averages (calculated from 2 to 3 total nitrogen values) were estimates. One of five annual averages was in violation of the objective.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for Deep Creek Station 5, from Lahontan Basin Plan Table 3-21, applies under the tributary rule. The objective includes an annual average total nitrogen concentration of 0.3 mg/L, and a 90th percentile value of 0.7 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples each (2 to 4 per year) were collected for total Kjeldahl nitrogen and nitrite plus nitrate.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76416, Nitrogen
Region 6     
Sheep Creek
 
LOE ID: 133514
 
Pollutant: Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed water quality data collected through the SWAMP program for Sheep Creek between 11/2010 and 4/2015 generally between 1-3 times per year. Five annual average values were calculated and 1 of 6 samples exceeded the site specific objective for Deep Creek, to which Sheep Creek is tributary. The annual averages (some of which are based on a single sample) ranged between ND to 0.47 mg/L Nitrogen as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Lahontan Region contains a site specific objective for nitrogen in Table 3-21 for Deep Creek below Lake of 0.3 mg/L as an annual average. Sheep Creek is a tributary to Deep Creek. There is no site specific objective for nitrogen for Sheep Creek so the Deep Creek objective applies due to the tributary rule.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The water quality samples were collected at station 628SHP001, Sheep Creek below Scout Camp.
Temporal Representation: Water quality data were collected through the SWAMP program for Sheep Creek between 11/2010 and 4/2015 generally between 1-3 times per year.
Environmental Conditions:
QAPP Information: Water Quality data were collected according to the Surface Water Ambient Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
102255
Region 6     
Sheep Creek
 
Pollutant: Nitrogen, Nitrite
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 Staff 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. 0 of 13 samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 13 samples exceeded the objective 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 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 102255, Nitrogen, Nitrite
Region 6     
Sheep Creek
 
LOE ID: 98582
 
Pollutant: Nitrogen, Nitrite
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Nitrite as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Lahontan Basin, Objective for Municipal and Domestic Supply uses of inland surface waters states the following: waters shall not contain concentrations of inorganic chemicals in excess of the limits specified in California Code of Regulations, Title 22, Table 64431-A of section 64431 (Inorganic Chemicals). The maximum contaminant level listed in Table 64431-A for Nitrite as N is 1.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-04-19 and 2011-04-19
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102255, Nitrogen, Nitrite
Region 6     
Sheep Creek
 
LOE ID: 7963
 
Pollutant: Nitrite as Nitrite NO2
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled nitrite under the Region 6 SWAMP program between 2001 and 2005. Of 23 quarterly samples, 6 had nitrite concentrations below the detection level and one was an estimated value. Nitrite concentrations in the remaining samples ranged from 0.001 to 0.007 mg/L. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for nitrite is mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
70972
Region 6     
Sheep Creek
 
Pollutant: Phosphate
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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. One of eleven samples exceed the site specific objective that applies to Sheep Creek due to the tributary rule.

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. One of eleven samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 70972, Phosphate
Region 6     
Sheep Creek
 
LOE ID: 7985
 
Pollutant: Phosphate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program between 2001 and 2005. Concentrations of PO4 in 12 samples included two estimated values and two values below the detection level.
Concentrations in the remaining samples ranged from 0.012 to 0.057 mg/L. In two of five years, samples were all estimates or below the detection level. Calculated annual average PO4 concentrations in the remaining samples were 0.014, 0.097 and 0.016 mg/L. The annual average objective was exceeded in one of 5 years.

Two additional samples were collected for dissolved hydrolyzable P plus PO4; one of these samples was 0.02 mg/L and the other was below the detection level.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for Deep Creek Station 5, from Lahontan Basin Plan Table 3-21, applies under the tributary rule. The objective includes an annual average total dissolved orthophosphate concentration of 0.05 mg/L, and a 90th percentile value of 0.13 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected for PO4 between 2001 and 2005 Two additional samples for dissolved hydrolyzable P plus PO4 in October 2001 and February 2002.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70972, Phosphate
Region 6     
Sheep Creek
 
LOE ID: 133515
 
Pollutant: Phosphate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold 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 data collected through the SWAMP program from 11/2010 through 4/2015. Six annual average values were calculated based on the available data and 0 of 6 samples exceeded the site specific objective for phosphate of 0.05 mg/L. The calculated annual averages ranged between 0.03 and 0.046 mg/L Phosphate.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Lahontan Region contains a site specific objective in Table 3-21 for Phosphate for Deep Creek below Lake of 0.05 mg/L as an annual average. Sheep Creek is a tributary to Deep Creek, so this objective applies due to the tributary rule.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The data were collected at station 628SHP001, Sheep Creek below Scout Camp.
Temporal Representation: The water quality samples were collected through the SWAMP program from 11/2010 through 4/2015 generally 1-3 times per year.
Environmental Conditions:
QAPP Information: The water quality data was collected according to the Surface Water Ambient Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
102257
Region 6     
Sheep Creek
 
Pollutant: Sodium
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 Staff 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.

Four lines of evidence, two which assess the available data for the AG beneficial use and two which assess the available data for the MUN beneficial use are available in the administrative record to assess this pollutant. 0 of 11 samples exceed the water quality objective for the AG beneficial use and 1 of 11 samples exceed the objective for the MUN beneficial use.

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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 11 samples exceed the water quality objective for the AG beneficial use and 1 of 11 samples exceed the objective for the MUN beneficial use, and these sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples per beneficial use assessed are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 102257, Sodium
Region 6     
Sheep Creek
 
LOE ID: 98143
 
Pollutant: Sodium
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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Sodium.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
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, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-04-19 and 2011-04-19
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102257, Sodium
Region 6     
Sheep Creek
 
LOE ID: 98520
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality standard for Sodium.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
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, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.
Guideline Reference: Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102257, Sodium
Region 6     
Sheep Creek
 
LOE ID: 97251
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 10
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 1 of 10 samples exceeded the water quality standard for Sodium.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
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, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 102257, Sodium
Region 6     
Sheep Creek
 
LOE ID: 97124
 
Pollutant: Sodium
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 RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Sodium.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
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, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.
Guideline Reference: 2012 Edition of the Drinking Water Standards and Health Advisories
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2011-04-19 and 2011-04-19
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
68801
Region 6     
Sheep Creek
 
Pollutant: Specific Conductivity
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. 0 of 22 samples exceeds the water quality objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and dissolved ion concentrations in streams of the Lahontan Region.
3. 0 of 22 samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 68801, Specific Conductivity
Region 6     
Sheep Creek
 
LOE ID: 97123
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water designated as MUN shall not contain concentrations of chemical constituents in excess of the maximum contaminant level (MCL) or secondary maximum contaminant level (SMCL) based upon drinking water standards specified in Title 22 of the California Code of Regulations (Water Quality Control Plan, Lahontan Region).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's \Chemical Constituents\" objective. The California Secondary MCL for specific conductivity is 900 uS/cm."
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 68801, Specific Conductivity
Region 6     
Sheep Creek
 
LOE ID: 5300
 
Pollutant: Specific Conductance
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey measured specific conductance under the Region 6 SWAMP program. Eleven laboratory measurements of specific conductance ranged from 118 to 249 uS/cm. Three field measurements ranged from 183 to 305 uS/cm. The objective was not exceeded.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for specific conductance is 900 microsiemens per centimeter (uS/cm).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Eleven laboratory measurements and three field measurements were taken approximately quarterly between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
70535
Region 6     
Sheep Creek
 
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: 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.

Three lines of evidence, two which assess the available data for the COLD beneficial use and one which assesses the available data for the MUN beneficial use, are available in the administrative record to assess this pollutant. 2 of 11 samples exceed the objective for the COLD beneficial use and 0 of 12 samples exceed the objective for the MUN beneficial use.

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 satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region.
3. 2 of 11 samples exceed the objective for the COLD beneficial use and 0 of 12 samples exceed the objective for the MUN beneficial use and these sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples per beneficial use assessed are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 70535, Sulfates
Region 6     
Sheep Creek
 
LOE ID: 5301
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled sulfate under the Region 6 SWAMP program between 2001 and 2005. Sulfate concentrations in 12 quarterly samples ranged from 1.3 to 9.5 mg/L. The MCL was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for sulfate is 250 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70535, Sulfates
Region 6     
Sheep Creek
 
LOE ID: 96625
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan Water Board staff conducting routine Surface Water Ambient Monitoring Program (SWAMP) sampling. Data were collected between November 2011 and April 2015. Concentrations in the raw data ranged from 2.02 to 3.08 mg/L. Six annual averages were computed, none of which exceeded the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for sulfates in Sheep Creek, as referenced in the Lahontan Basin Plan table 3-21, is an annual average not to exceed 3.4 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 628SHP001, which is located below the Scout Camp off of Deep Creek Camp Road.
Temporal Representation: Data were collected beginning in November 2010, and were collected three times per calendar year in the spring, summer and fall in 2011 and 2012. One field visit was made each year in the spring of 2013, 2014 and 2015.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
Line of Evidence (LOE) for Decision ID 70535, Sulfates
Region 6     
Sheep Creek
 
LOE ID: 5302
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled sulfate under the Region 6 SWAMP program. Sulfate concentrations in 12 samples ranged from 1.3 to 9.5 mg/L. The annual average objective was violated in two of five years.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site-specific objective from Lahontan Basin Plan Table 3-21 includes an annual average sulfate concentration of 3.4 mg/L, and a 90th percentile value of 6.9 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
102258
Region 6     
Sheep Creek
 
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 Staff 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. 0 of 11 samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 11 samples exceeded the objective 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 are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 102258, Turbidity
Region 6     
Sheep Creek
 
LOE ID: 98580
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality standard for Turbidity.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water designated as MUN shall not contain concentrations of chemical constituents in excess of the maximum contaminant level (MCL) or secondary maximum contaminant level (SMCL) based upon drinking water standards specified in Title 22 of the California Code of Regulations. The Lahontan Basin Plan also has regionwide turbidity objective for other beneficial uses that states: Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10%.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient surface waters under the Lahontan Basin Plan's \Chemical Constituents\" objective. The Secondary MCL for turbidity is 5 NTU. Calculation of a numeric objective for other beneficial uses requires comparison with upstream or other background data which may not be available as part of the data used for water quality assessment. "
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
70123
Region 6     
Sheep Creek
 
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 Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff 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.

Four lines of evidence is available in the administrative record to assess this pollutant. pH assessments require background information regarding water quality conditions in the waterbody to assess changes to ambient pH. These information were not available for the 2018 assessment and the computed sample size for 2018 data is zero. 0 of 11 samples from a previous assessment cycle exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 11 samples exceeded the objective 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 are 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 70123, pH
Region 6     
Sheep Creek
 
LOE ID: 5306
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled pH under the Region 6 SWAMP program between 2001 and 2005. Eleven pH measurements ranged from 7 to 7.5 units. There were too few samples to define the normal pH regime or to allow detection of change.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Lahontan Basin Plan's objective for pH states: "In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units.

The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Eleven field pH measurements were taken approximately quarterly between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70123, pH
Region 6     
Sheep Creek
 
LOE ID: 129539
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 0 of 0 samples exceeded the water quality standard for pH. Although pH data does exist for this waterbody, the objective for this pollutant requires background information that is currently unavailable, and therefore an assessment of water quality standards could not be made.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Lahontan Basin Plan's regionwide objective for pH states: \In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis.\""
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 70123, pH
Region 6     
Sheep Creek
 
LOE ID: 129846
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 0 of 0 samples exceeded the water quality standard for pH. Although pH data does exist for this waterbody, the objective for this pollutant requires background information that is currently unavailable, and therefore an assessment of water quality standards could not be made.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Lahontan Basin Plan's regionwide objective for pH states: \In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis.\""
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 70123, pH
Region 6     
Sheep Creek
 
LOE ID: 129542
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 0 of 0 samples exceeded the water quality standard for pH. Although pH data does exist for this waterbody, the objective for this pollutant requires background information that is currently unavailable, and therefore an assessment of water quality standards could not be made.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Lahontan Basin Plan's regionwide objective for pH states: \In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis.\""
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
70477
Region 6     
Sheep Creek
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: 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 Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2031
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: 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.

Six lines of evidence, one evaluating dissolved oxygen saturation data for the COLD beneficial use, three evaluating dissolved oxygen data for the COLD beneficial use and two evaluating dissolved oxygen data for the WARM beneficial use, are available in the administrative record to assess this pollutant. 0 of 3 dissolved oxygen saturation samples exceed the objective for the COLD beneficial use; 9 of 32 dissolved oxygen samples exceed the objective for the COLD beneficial use; 8 of 22 dissolved oxygen samples exceed the objective for the WARM beneficial use.

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

This conclusion is based on the staff findings that:
1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 9 of 32 dissolved oxygen samples exceed the objective for the COLD beneficial use; 8 of 22 dissolved oxygen samples exceed the objective for the WARM beneficial use and these sample sizes 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 Staff 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.
 
 
Line of Evidence (LOE) for Decision ID 70477, Oxygen, Dissolved
Region 6     
Sheep Creek
 
LOE ID: 130154
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold 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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 8 of 11 samples exceeded the water quality standard for Oxygen, Saturation.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Lahontan Region's water quality objective states that the dissolved oxygen concentration shall not be less than 80 percent of saturation.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 70477, Oxygen, Dissolved
Region 6     
Sheep Creek
 
LOE ID: 129946
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: For waters with the beneficial uses of COLD, COLD with SPWN, WARM, and WARM with SPWN, the minimum dissolved oxygen concentration shall not be less than that specified in Table 3-6. (Water Quality Control Plan, Lahontan Region)
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 70477, Oxygen, Dissolved
Region 6     
Sheep Creek
 
LOE ID: 129994
 
Pollutant: Oxygen, Dissolved
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 SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 8 of 11 samples exceeded the water quality standard for Oxygen, Saturation.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Lahontan Region's water quality objective states that the dissolved oxygen concentration shall not be less than 80 percent of saturation.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 70477, Oxygen, Dissolved
Region 6     
Sheep Creek
 
LOE ID: 5305
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey samplex dissolved oxygen under the Region 6 SWAMP program between 2001 and 2005. Dissolved oxygen concentrations in 10 samples ranged from 3.7 to 10.1 mg/L. One sample was below the 1-day minimum objective.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The applicable water quality objective from Lahontan Basin Plan Table 3-6 is a 1-day minimum concentration is 4.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station, Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead, was sampled.
Temporal Representation: Ten samples were collected approximately quarterly between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70477, Oxygen, Dissolved
Region 6     
Sheep Creek
 
LOE ID: 5820
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled percent saturation of dissolved oxygen under the Region 6 SWAMP program in 2004 and 2005. Percent saturation in three samples ranged from 93 to 100 percent. The objective was not violated.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The water quality objective in the Lahontan Basin Plan states that percent saturation shall not be depressed by more than 10 percent and the minimum dissolved oxygen concentration shall not be less than 80 percent saturation.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Three samples were collected quarterly between November 2004 and July 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70477, Oxygen, Dissolved
Region 6     
Sheep Creek
 
LOE ID: 130117
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Sheep Creek to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP RWB6 Monitoring (tissue and water).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: For waters with the beneficial uses of COLD, COLD with SPWN, WARM, and WARM with SPWN, the minimum dissolved oxygen concentration shall not be less than that specified in Table 3-6. (Water Quality Control Plan, Lahontan Region)
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (628SHP001)
Temporal Representation: The samples were collected between the dates of 2010-11-09 and 2015-04-14
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
75384
Region 6     
Sheep Creek
 
Pollutant: Phosphorus
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 Staff Conclusion: Regional Board Conclusion:

This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle.

No new information was reviewed for this current assessment 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 are available in the administrative record to assess this pollutant. No biological data are available for assessment whether any of the chemical samples exceeds the water quality objective for biostimulatory substances.

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 do not satisfy the data quality requirements of section 6.1.4 of the Policy due to an error in the SWAMP QAPP regarding holding times for total phosphorus samples.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region.
3. No biological data are available for assessment of compliance with the water quality objective and the data cannot be assessed using 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 Staff Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
 
Line of Evidence (LOE) for Decision ID 75384, Phosphorus
Region 6     
Sheep Creek
 
LOE ID: 8046
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program between 2002 and 2005. One of 8 quarterly samples for total phosphorus was an estimated value and two samples were below the detection level. Concentrations of total phosphorus in the remaining samples ranged from 0.033 to 0.072 mg/L. No biological data are available for assessment of compliance with the objective for biostimulatory substances.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There is no site-specific numeric objective for total phosphorus for Sheep Creek. The Lahontan Basin Plan's narrative objective for biostimulatory substances states:

"Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Eight quarterly samples (1 to 4 per year) were collected between 2002 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Sampling and analysis were done according to the SWAMP QAPP. However, in July 2009 an error was discovered in the QAPP related to holding times for total phosphorus samples that affects the validity of data for the Lahontan Region The holding time for samples that are not acid-preserved.should be 48 hours rather than 28 days as indicated in the QAPP. "Low level" phosphorus analyses, without acid preservation, are used in the Lahontan Region's SWAMP program. .
QAPP Information Reference(s):
 
 
DECISION ID
70076
Region 6     
Sheep Creek
 
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 Staff Conclusion: Regional Board Conclusion:

This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle.

No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows:

The Lahontan Basin Plan's narrative temperature objective is an antidegradation-based objective that requires that there be no change in temperature in waters designated for the Cold Freshwater Habitat (COLD) beneficial use. The objective does not include specific numerical limits for protection of the COLD use. Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects.

One line of evidence is available to support this decision. There are not enough temperature samples to establish baseline conditions (including diel, seasonal, annual and interannual variations in temperature) or to detect declining trends in the temperature regime if such trends exist.

Because temperature samples were collected only quarterly, weekly and monthly average data are not available for comparison with guidelines in the scientific literature for the temperature requirements of sensitive aquatic species such as salmonids, as directed in Listing Policy Section 6.1.5.9.
 
Regional Board Staff Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
 
Line of Evidence (LOE) for Decision ID 70076, Temperature, water
Region 6     
Sheep Creek
 
LOE ID: 5307
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey measured water temperature under the Region 6 SWAMP program between 2001 and 2005. Temperatures in 12 measurements ranged from 3.5 to 17 degrees Celsius. Sampling frequency was insufficient to allow determination of the natural temperature regime or to detect changes.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The relevant language from the Lahontan Basin Plan's temperature objective is as follows: "The natural receiving water temperature of a l waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses.

For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit ... above or below the natural temperature. For waters designated COLD, the temperature shall not be altered."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve temperature measurements were taken between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
 
 
DECISION ID
75385
Region 6     
Sheep Creek
 
Pollutant: Total Kjeldahl Nitrogen (TKN)
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 Staff Conclusion: Regional Board Conclusion:

This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle.

No new information was reviewed for this current assessment 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. No biological data are available to assess whether any of the chemical samples exceeds the water quality objective for biostimultory substances.

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 satisfy the data quality requirements of section 6.1.4 of the Policy.
2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region.
3. No biological data are available for assessment of compliance with the water quality objective and the data cannot be assessed using 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 Staff Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
 
Line of Evidence (LOE) for Decision ID 75385, Total Kjeldahl Nitrogen (TKN)
Region 6     
Sheep Creek
 
LOE ID: 8047
 
Pollutant: Total Kjeldahl Nitrogen (TKN)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: The U.S. Geological Survey sampled Sheep Creek under the Region 6 SWAMP program between 2001 and 2005. One of 12 quarterly sampling results for TKN was below the detection level and 4 samples were estimated values. Concentrations of TKN in the remaining samples ranged from 0.06 to 0.46 mg/L. No biological data are available for assessment of compliance with the objective for biostimulatory substances.
Data Reference: 2007. SWAMP Data for the Mojave River Watershed
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: There is no site-specific numeric objective for Total Kjeldahl Nitrogen (TKN) for Sheep Creek. The Lahontan Basin Plan's narrative objective for biostimulatory substances states:

"Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One station was sampled: "Sheep Creek below Lake Arrowhead Scout Camp near Lake Arrowhead."
Temporal Representation: Twelve quarterly samples (2 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: Sheep Creek is a tributary of Deep Creek, the largest tributary of the Mojave River, located in San Bernardino National Forest. Sheep Creek is designated for both the Cold Freshwater Habitat and the Warm Freshwater Habitat beneficial uses.
QAPP Information: Data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):