Final California 2010 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Willow Creek (Lassen County, Central Valley)
Water Body ID: CAR5266107220090110153757
Water Body Type: River & Stream
 
DECISION ID
9640
Region 5     
Willow Creek (Lassen County, Central Valley)
 
Pollutant: Chloride
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 3 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 3 has 2 or more samples that exceed the evaluation criteria.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 9640, Chloride
Region 5     
Willow Creek (Lassen County, Central Valley)
 
LOE ID: 20912
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of the 3 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for Chloride.
Data Reference: SWAMP data entered by SWRCB into BDAT database
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: Chloride levels should not exceed 250 mg/L (Department of Public Health Secondary MCL).
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: Samples were collected at Lower Willow Creek. Samples were collected at Middle Willow Creek. Samples were collected at Upper Willow Creek.
Temporal Representation: The samples were collected from October 14 2003 to October 15 2003.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
9645
Region 5     
Willow Creek (Lassen County, Central Valley)
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for listing under sections 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 43 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.2 of the Listing Policy. Table 3.2 of the listing policy recommends listing if a sample size of 43 has 8 or more samples that exceed the evaluation criteria.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 9645, Specific Conductivity
Region 5     
Willow Creek (Lassen County, Central Valley)
 
LOE ID: 20966
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 42
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: None of the 42 samples collected by the Surface Water Ambient Monitoring Program exceeded the "recommended" Secondary MCL of 900 uS/cm for electrical conductivity.
Data Reference: SWAMP data entered by SWRCB into BDAT database
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The secondary MCLs for electrical conductivity provide a range of values including a "recommended" level (900 uS/cm), upper level (1600 uS/cm) and a short-term level (2200 uS/cm). The “recommended” concentration was used as it is intended to be protective of all drinking water uses
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Lower Willow Creek, Middle Willow Creek, and Upper Willow Creek
Temporal Representation: The samples were collected from Jan 16 2003 to Sep 27 2006
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
9648
Region 5     
Willow Creek (Lassen County, Central Valley)
 
Pollutant: Total Dissolved Solids
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for listing under sections 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 0 of 3 available concentrations exceeded the water quality objective and this does not exceed the allowable frequency using Table 3.1 of the Listing Policy. Table 3.1 of the listing policy recommends listing if a sample size of 3 has 2 or more samples that exceed the evaluation criteria.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 9648, Total Dissolved Solids
Region 5     
Willow Creek (Lassen County, Central Valley)
 
LOE ID: 20871
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: none of the 3 samples collected by the Surface Water Ambient Monitoring Program exceeded the "recommended" Seconsdary MCL of 500 mg/L for Total Dissolved Solids
Data Reference: SWAMP data entered by SWRCB into BDAT database
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The secondary MCL’s for Total Dissolved Solids provide a range of values including a recommended level (500 mg/L), upper level (1000 mg/L) and a short-term level (1500 mg/L). The “recommended” concentration was used as it is intended to be protective of all drinking water uses
Objective/Criterion Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from Lower Willow Creek, Middle Willow Creek, and Upper Willow Creek
Temporal Representation: The samples were collected between October 14, 2003 and October 15, 2003
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
16275
Region 5     
Willow Creek (Lassen County, Central Valley)
 
Pollutant: Escherichia coli (E. coli)
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Eighteen of the samples exceed the water quality objective.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eighteen of 37 available concentrations exceeded the USEPA E. Coli Guideline for Water Contact Recreation and this does exceed the allowable frequency using Table 3.2 of the Listing Policy. In addition, 16 of 37 available concentrations exceeded the USEPA E. Coli Guideline for Non-Contact Recreation and this does exceed the allowable frequency using Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 16275, Escherichia coli (E. coli)
Region 5     
Willow Creek (Lassen County, Central Valley)
 
LOE ID: 27892
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 37
Number of Exceedances: 16
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Sixteen of the 37 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for E.Coli Bacteria. The exceeded results are as follows: 7/13/2004 - a sample taken at Lower Willow Creek had a result of 461MPN/100 mL. 8/17/2004 - a sample taken at Lower Willow Creek had a result of 980MPN/100 mL. 9/14/2004 - a sample taken at Lower Willow Creek had a result of 687MPN/100 mL. 5/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Lower Willow Creek had a result of 1200MPN/100 mL. 8/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 5/21/2004 - a sample taken at Middle Willow Creek had a result of 613MPN/100 mL. 6/18/2004 - a sample taken at Middle Willow Creek had a result of 1410MPN/100 mL. 7/21/2004 - a sample taken at Middle Willow Creek had a result of >=2420MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 649MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 816MPN/100 mL. 5/16/2005 - a sample taken at Middle Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Middle Willow Creek had a result of 488MPN/100 mL. 7/18/2005 - a sample taken at Middle Willow Creek had a result of 921MPN/100 mL. 8/15/2005 - a sample taken at Middle Willow Creek had a result of 727MPN/100 mL. 1/19/2005 - a sample taken at Upper Willow Creek had a result of 613MPN/100 mL.
Data Reference: SWAMP data entered by SWRCB into BDAT database
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: E.Coli Bacteria levels should not exceed 409 MPN/100 mL in any single sample (USEPA E.Coli Guideline)
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at Lower Willow Creek. Samples were collected at Middle Willow Creek. Samples were collected at Upper Willow Creek.
Temporal Representation: The samples were collected from May 2004 to September 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 16275, Escherichia coli (E. coli)
Region 5     
Willow Creek (Lassen County, Central Valley)
 
LOE ID: 27893
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 37
Number of Exceedances: 18
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Eighteen of the 37 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for E.Coli Bacteria. The exceeded results are as follows: 6/18/2004 - a sample taken at Lower Willow Creek had a result of 276MPN/100 mL. 7/13/2004 - a sample taken at Lower Willow Creek had a result of 461MPN/100 mL. 8/17/2004 - a sample taken at Lower Willow Creek had a result of 980MPN/100 mL. 9/14/2004 - a sample taken at Lower Willow Creek had a result of 687MPN/100 mL. 5/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Lower Willow Creek had a result of 1200MPN/100 mL. 7/18/2005 - a sample taken at Lower Willow Creek had a result of 387MPN/100 mL. 8/16/2005 - a sample taken at Lower Willow Creek had a result of >2420MPN/100 mL. 5/21/2004 - a sample taken at Middle Willow Creek had a result of 613MPN/100 mL. 6/18/2004 - a sample taken at Middle Willow Creek had a result of 1410MPN/100 mL. 7/21/2004 - a sample taken at Middle Willow Creek had a result of >=2420MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 649MPN/100 mL. 8/17/2004 - a sample taken at Middle Willow Creek had a result of 816MPN/100 mL. 5/16/2005 - a sample taken at Middle Willow Creek had a result of >2420MPN/100 mL. 6/20/2005 - a sample taken at Middle Willow Creek had a result of 488MPN/100 mL. 7/18/2005 - a sample taken at Middle Willow Creek had a result of 921MPN/100 mL. 8/15/2005 - a sample taken at Middle Willow Creek had a result of 727MPN/100 mL. 1/19/2005 - a sample taken at Upper Willow Creek had a result of 613MPN/100 mL.
Data Reference: SWAMP data entered by SWRCB into BDAT database
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. (CRWQCB, 2006)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline: E.Coli Bacteria levels should not exceed 235 MPN/100 mL in any single sample (USEPA E.Coli Guideline)
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Samples were collected at Lower Willow Creek. Samples were collected at Middle Willow Creek. Samples were collected at Upper Willow Creek.
Temporal Representation: The samples were collected from May 2004 to September 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):
 
 
DECISION ID
9788
Region 5     
Willow Creek (Lassen County, Central Valley)
 
Pollutant: pH
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for listing under sections 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Data is available from 1 line of evidence for this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollution combination on the section 303(d) list. The recommendation is based on staff findings that 9 of 53 available concentrations exceeded the water quality objective and this does exceed the allowable frequency using Table 3.2 of the Listing Policy. Table 3.2 of the listing policy recommends listing if a sample size of 53 has 9 or more samples that exceed the evaluation criteria.

The data used satisfies the data quality requirements of section 6.1.4 of the Policy. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
USEPA Action (if applicable): USEPA approved the listing of this water body as a water quality limited segment requiring a TMDL for this pollutant.
 
 
Line of Evidence (LOE) for Decision ID 9788, pH
Region 5     
Willow Creek (Lassen County, Central Valley)
 
LOE ID: 21179
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 53
Number of Exceedances: 9
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Nine of the 53 samples collected by the Surface Water Ambient Monitoring Program exceeded the evaluation objective for pH.
Data Reference: SWAMP data entered by SWRCB into BDAT database
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: pH levels should not be lower than 6.5 or higher than 8.5 (Basin Plan Objective)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins. 4th ed
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Lower Willow Creek. Samples were collected at Middle Willow Creek. Samples were collected at Upper Willow Creek.
Temporal Representation: The samples were collected from January 2003 to August 2005.
Environmental Conditions:
QAPP Information: Monitoring was conducted in accordance with the State Water Resources Control Board's Quality Assurance Program Plan for the State of California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s):