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

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name: Squaw Creek
Water Body ID: CAR6352001119980805095744
Water Body Type: River & Stream
 
DECISION ID
102113
Region 6     
Squaw 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: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 6 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 6 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102113, Alkalinity as CaCO3
Region 6     
Squaw Creek
 
LOE ID: 98116
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
102118
Region 6     
Squaw 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 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.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 7 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 7 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102118, Ammonia
Region 6     
Squaw Creek
 
LOE ID: 98689
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Truckee River Watershed Council data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 7 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 Truckee River Watershed Council.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (MTRSQCR00)
Temporal Representation: The samples were collected between the dates of 2011-05-14 and 2016-09-22
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
 
DECISION ID
103415
Region 6     
Squaw Creek
 
Pollutant: Benthic Community Effects
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects.

Two lines of evidence evaluating benthic-macroinvertebrate bioassessment data are available in the administrative record to assess this indicator. 1 of 8 benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold.These data indicate that the waterbody is likely unimpaired and therefore no other pollutant LOEs need be associated with this decision at this time.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing Benthic Community Effects in this waterbody segment on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 1 of 8 benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. Therefore, this water body is not exceeding the water quality threshold for the protection of the COLD beneficial use. The available information indicates that the waterbody/pollutant combination should not be placed on the 303(d) List of impaired waters at this time.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 103415, Benthic Community Effects
Region 6     
Squaw Creek
 
LOE ID: 96781
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: The site had a CSCI score of 1.088256 and 1.20989. This score indicates that this site is supporting aquatic life beneficial uses and that the water quality objective is met. Additionally, this water body passed several screening criteria and was identified as a reference water body for the purposes of developing the CSCI. Reference sites where human disturbance is absent or minimal are used to set benchmark expectations for healthy streams. A large set of nearly 600 reference sites representing the broad diversity of natural stream types found across California was used to develop the CSCI.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Perennial Stream Surveys.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples collected at site 635SQN001
.
Temporal Representation: Samples collected on 8/28/2000 and 7/9/2001.
Environmental Conditions:
QAPP Information: QAPP for SWAMP Perennial Stream Surveys
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 103415, Benthic Community Effects
Region 6     
Squaw Creek
 
LOE ID: 96503
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 1
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The CSCI scores from this water body were
0.851333649
0.775140981
1.13543373
1.031751119
1.049510107
0.963968816

One of the six scores is not meeting the water quality objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Water Quality Monitoring Plan.
 
SWAMP Data:
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples collected from the following stations:
BIO-SC1
BIO-SC2
BIO-SC3
Temporal Representation: Samples collected on the following dates:
6/27/2014
7/25/2012
7/24/2012
6/27/2014
7/23/2012
6/26/2014
Environmental Conditions:
QAPP Information: QAPP for Truckee River Watershed Council
QAPP Information Reference(s): Sampling and Analysis Plan for Implementation of the Truckee River Water Quality Monitoring Plan Water Year 2014
 
 
DECISION ID
68769
Region 6     
Squaw 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 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 are available in the administrative record to assess this pollutant. 2 of 3 samples evaluated for the COLD beneficial use and 0 of 3 samples evaluated for the MUN beneficial use exceeds the applicable 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 or Table 3.2 of the Policy.
3. 2 of 3 samples evaluated for the COLD beneficial use and 0 of 3 samples evaluated for the MUN beneficial use exceeds the applicable water quality objective 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 68769, Chloride
Region 6     
Squaw Creek
 
LOE ID: 96838
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan SWAMP staff for routine regional monitoring at one location in 2014 and 2015. Concentrations in the raw data ranged from 2.09 to 5.66 mg/L. Two annual averages can be computed, both of which exceed the water quality objective for chloride.
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 Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration not to exceed 3.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected at one location, 635SQLB01, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in September and October 2014 and in January, April, September and December 2015.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 68769, Chloride
Region 6     
Squaw Creek
 
LOE ID: 26279
 
Pollutant: Chloride
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: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. Chloride concentrations were 1.7, 1.8, and 1.8 mg/L. The mean concentration for this month was 1.8 mg/L The water quality objective was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for chloride, from Lahontan Basin Plan Table 3-11, is 3.0 mg/L as a mean of monthly means for the period of record.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 68769, Chloride
Region 6     
Squaw Creek
 
LOE ID: 26281
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. Chloride concentrations were 1.7, 1.8, and 1.8 mg/L. The MCL was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-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: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data..
QAPP Information Reference(s):
 
 
DECISION ID
102116
Region 6     
Squaw Creek
 
Pollutant: Fluoride
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 6 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 6 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102116, Fluoride
Region 6     
Squaw Creek
 
LOE ID: 98167
 
Pollutant: Fluoride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
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 SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality standard for Fluoride.
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 Fluoride incorporated by reference in the Water Quality Control Plan, Lahontan Region is 2 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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
102114
Region 6     
Squaw Creek
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.2 and 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status.

Nine lines of evidence, three which evaluated E. coli data for the REC-1 beneficial use and six which evaluated fecal coliform data for the MUN beneficial use, are available in the administrative record to assess this pollutant. 0 of 20 E. coli samples and 2 of 39 fecal coliform samples exceed the water quality objectives.

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. 0 of 20 E. coli samples and 2 of 39 fecal coliform samples exceed the water quality objectives and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 129166
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 1 of the 9 samples exceeded the logmean water quality standard for Coliform, Fecal. This is a 30-day rolling logmean that is calculated daily.
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: Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml. (Lahontan Region Basin Plan)
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), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2014-09-23 and 2015-09-16 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 129234
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 1 of the 9 samples exceeded the water quality standard for Coliform, Fecal. The water quality standard is based on a 10% exceedance rate that is calculated monthly.
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: Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. (Lahontan Region Basin Plan)
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), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2014-09-23 and 2015-09-16 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 129334
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB6_BACT_Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the logmean water quality standard for Coliform, Fecal. This is a 30-day rolling logmean that is calculated daily.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Regional Water Board 6 Bacteria Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml. (Lahontan Region Basin Plan)
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), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2013-08-05 and 2014-10-03 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 129435
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Truckee River Watershed Council data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the water quality standard for Coliform, Fecal. The water quality standard is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Watershed Council.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. (Lahontan Region Basin Plan)
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), station(s): MTRSQCR00
Temporal Representation: The samples were collected between the days of 2011-05-14 and 2016-05-14 .
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 99873
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the Statistical Threshold Value (STV) water quality standard for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
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 bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2014-09-23 and 2015-09-16 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 99999
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB6_BACT_Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the geomean water quality standard for E. coli. This is a six week rolling geomean that is calculated weekly.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Regional Water Board 6 Bacteria Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a six-week rolling GEOMETRIC MEAN (GM) of Escherichia coli (E. coli) not to exceed 100 colony forming units per 100 milliliters (cfu/100 mL) (calculated weekly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2013-08-05 and 2014-10-03 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 99982
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB6_BACT_Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the Statistical Threshold Value (STV) water quality standard for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Regional Water Board 6 Bacteria Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all waters, except Lake Tahoe, where the salinity is less than 10 parts per thousand (ppth) 95 percent or more of the time is a STATISTICAL THRESHOLD VALUE (STV) of 320 cfu/100 mL not to be exceeded more than 10 percent of the time (calculated monthly).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2013-08-05 and 2014-10-03 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 129354
 
Pollutant: Fecal Coliform
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: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB6_BACT_Monitoring data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the water quality standard for Coliform, Fecal. The water quality standard is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for Regional Water Board 6 Bacteria Monitoring.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. (Lahontan Region Basin Plan)
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), station(s): 635SQLB01
Temporal Representation: The samples were collected between the days of 2013-08-05 and 2014-10-03 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102114, Indicator Bacteria
Region 6     
Squaw Creek
 
LOE ID: 129433
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Truckee River Watershed Council data for Squaw Creek to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the logmean water quality standard for Coliform, Fecal. This is a 30-day rolling logmean that is calculated daily.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Watershed Council.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml. (Lahontan Region Basin Plan)
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), station(s): MTRSQCR00
Temporal Representation: The samples were collected between the days of 2011-05-14 and 2016-05-14 .
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
 
DECISION ID
102117
Region 6     
Squaw 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: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. 0 of 14 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 14 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102117, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Squaw Creek
 
LOE ID: 97384
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Truckee River Watershed Council data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 8 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 Truckee River Watershed Council.
 
SWAMP Data: Non-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) (MTRSQCR00)
Temporal Representation: The samples were collected between the dates of 2011-05-14 and 2016-09-22
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
Line of Evidence (LOE) for Decision ID 102117, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Squaw Creek
 
LOE ID: 98550
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
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 SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
102132
Region 6     
Squaw Creek
 
Pollutant: Nitrogen
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 2 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 2 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102132, Nitrogen
Region 6     
Squaw Creek
 
LOE ID: 96839
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: Data were collected by Lahontan SWAMP staff for routine regional monitoring at one location in 2014 and 2015. Concentrations in the raw data ranged from 0.0298 to 0.0918 mg/L. Two annual averages can be computed, both of which attain the water quality objective for total nitrogen.
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 nitrogen in Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration not to exceed 0.18 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected at one location, 635SQLB01, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in September and October 2014 and in January, April, September and December 2015.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
76661
Region 6     
Squaw Creek
 
Pollutant: Nitrogen, Nitrate
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 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.

Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeds the California Maximum Contaminant Level (MCL). The single monthly mean datapoint exceeds the site-specific 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. All samples were collected on a single day.
3. None of three samples exceeded the MCL The single monthly mean exceeded the site-specific objective. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 76661, Nitrogen, Nitrate
Region 6     
Squaw Creek
 
LOE ID: 26284
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. NO3-N concentrations were 0.12, 0.14, and 0.23 mg/L. The mean concentration for this month was 0.16 mg/L, in violation of the objective.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for nitrate (NO3-N), from Lahontan Basin Plan Table 3-11, is 0.05 mg/L as a mean of monthly means for the period of record.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 76661, Nitrogen, Nitrate
Region 6     
Squaw Creek
 
LOE ID: 26285
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. NO3-N concentrations were 0.12, 0.14, and 0.23 mg/L. The MCL was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-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 to 10 mg/L expressed "as N."
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
 
DECISION ID
102121
Region 6     
Squaw Creek
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Three lines of evidence, two which evaluate dissolved oxygen data and one which evaluates dissolved oxygen saturation data are available in the administrative record to assess this pollutant. 0 of 29 dissolved oxygen samples exceed the water quality objective; 1 of 6 dissolved oxygen saturation samples exceed the 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 29 dissolved oxygen samples exceed the water quality objective; 1 of 6 dissolved oxygen saturation samples exceed the 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102121, Oxygen, Dissolved
Region 6     
Squaw Creek
 
LOE ID: 130150
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 Truckee River Water Quality Monitoring Plan data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 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 Truckee River Water Quality Monitoring Plan.
 
SWAMP Data: Non-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 3 monitoring site(s) (BIO-SC1, BIO-SC2, BIO-SC3)
Temporal Representation: The samples were collected between the dates of 2012-07-23 and 2014-06-27
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Water Quality Monitoring Plan
QAPP Information Reference(s): Sampling and Analysis Plan for Implementation of the Truckee River Water Quality Monitoring Plan Water Year 2014
 
Line of Evidence (LOE) for Decision ID 102121, Oxygen, Dissolved
Region 6     
Squaw Creek
 
LOE ID: 130151
 
Pollutant: Oxygen, Dissolved
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 Truckee River Water Quality Monitoring Plan data for Squaw Creek to determine beneficial use support and results are as follows: 1 of 6 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 Truckee River Water Quality Monitoring Plan.
 
SWAMP Data: Non-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 3 monitoring site(s) (BIO-SC1, BIO-SC2, BIO-SC3)
Temporal Representation: The samples were collected between the dates of 2012-07-23 and 2014-06-27
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Water Quality Monitoring Plan
QAPP Information Reference(s): Sampling and Analysis Plan for Implementation of the Truckee River Water Quality Monitoring Plan Water Year 2014
 
Line of Evidence (LOE) for Decision ID 102121, Oxygen, Dissolved
Region 6     
Squaw Creek
 
LOE ID: 130082
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 23
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Truckee River Watershed Council data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 23 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 Truckee River Watershed Council.
 
SWAMP Data: Non-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) (MTRSQCR00)
Temporal Representation: The samples were collected between the dates of 2010-09-25 and 2016-09-22
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
 
DECISION ID
102127
Region 6     
Squaw Creek
 
Pollutant: Phosphorus
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. 0 of 8 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 8 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102127, Phosphorus
Region 6     
Squaw Creek
 
LOE ID: 96840
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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: Data were collected by Lahontan SWAMP staff for routine regional monitoring at one location in 2014 and 2015. Concentrations in the raw data ranged from non-detect to 0.006 mg/L. Two annual averages can be computed, both of which attain the water quality objective for phosphorous.
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 phosphorus in Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration not to exceed 0.02 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected at one location, 635SQLB01, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in September and October 2014 and in January, April, September and December 2015.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102127, Phosphorus
Region 6     
Squaw Creek
 
LOE ID: 96843
 
Pollutant: Phosphorus
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 the Truckee River Watershed Council between May 2011 and September 2016. Concentrations in the raw data ranged from 0.009 to 0.02 mg/L. Six annual averages can be computed, none of which exceed the water quality objective for phosphorus.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Watershed Council.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site specific objective for phosphorous in Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration not to exceed 0.02 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected at one location, MTRSQCR00, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in in May of 2011, 2012, 2013; in May and September of 2014; in May and June of 2015; and in May and September of 2016.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the Truckee River Monitoring Plan QAPP.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
 
DECISION ID
102128
Region 6     
Squaw 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 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.

Two lines of evidence which evaluate the available data against the MUN and AG beneficial uses are available in the administrative record to assess this pollutant. 0 of 6 samples in each evaluation 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 6 samples in either beneficial use evaluation 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102128, Sodium
Region 6     
Squaw Creek
 
LOE ID: 98598
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
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 SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102128, Sodium
Region 6     
Squaw Creek
 
LOE ID: 97173
 
Pollutant: Sodium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
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 SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
102130
Region 6     
Squaw Creek
 
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 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.

Two lines of evidence are available in the administrative record to assess this pollutant. 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 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. 0 of 12 samples exceeded the 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102130, Specific Conductivity
Region 6     
Squaw Creek
 
LOE ID: 98637
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
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 Truckee River Water Quality Monitoring Plan data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Water Quality Monitoring Plan.
 
SWAMP Data: Non-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 3 monitoring site(s) (BIO-SC1, BIO-SC2, BIO-SC3)
Temporal Representation: The samples were collected between the dates of 2012-07-23 and 2014-06-27
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Water Quality Monitoring Plan
QAPP Information Reference(s): Sampling and Analysis Plan for Implementation of the Truckee River Water Quality Monitoring Plan Water Year 2014
 
Line of Evidence (LOE) for Decision ID 102130, Specific Conductivity
Region 6     
Squaw Creek
 
LOE ID: 97263
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
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 SWAMP RWB6 Monitoring data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 6 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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
75844
Region 6     
Squaw 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 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 are available in the administrative record to assess this pollutant. 2 of 3 samples evaluated for the COLD beneficial use and 0 of 3 samples evaluated for the MUN beneficial use exceed the water quality objectives.

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 or Table 3.2 of the Policy.
3. 2 of 3 samples evaluated for the COLD beneficial use and 0 of 3 samples evaluated for the MUN beneficial use exceeded the objectives 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 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 75844, Sulfates
Region 6     
Squaw Creek
 
LOE ID: 26286
 
Pollutant: Sulfates
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: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. Sulfate concentrations were 9.2, 10.4 and 10.4 mg/L. The mean concentration for this month was 10.0 mg/L The water quality objective was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for sulfate, from Lahontan Basin Plan Table 3-11, is 25.0 mg/L as a mean of monthly means for the period of record.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75844, Sulfates
Region 6     
Squaw Creek
 
LOE ID: 96841
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan SWAMP staff for routine regional monitoring at one location in 2014 and 2015. Concentrations in the raw data ranged from 10.8 to 85.6 mg/L. Two annual averages can be computed, both of which exceed the water quality objective for phosphorous.
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 Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration not to exceed 25.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected at one location, 635SQLB01, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in September and October 2014 and in January, April, September and December 2015.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75844, Sulfates
Region 6     
Squaw Creek
 
LOE ID: 26287
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. Sulfate concentrations were 9.2, 10.4 and 10.4 mg/L. The MCL was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-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: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
 
DECISION ID
75845
Region 6     
Squaw Creek
 
Pollutant: Total Dissolved Solids
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 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 TDS data for the COLD beneficial use and one which assesses TDS data for the MUN beneficial use, are available in the administrative record to assess this pollutant. None of the samples exceeds the California Maximum Contaminant Level (MCL) for the MUN beneficial use assessment. 1 of 3 annual average sample exceed the objective for the COLD beneficial use assessment.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 3 samples exceeded the California MCL and 1 of 3 samples exceed the site specific objective assessed for the COLD beneficial use. These sample sizes are insufficient to determine if the beneficial uses are 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 75845, Total Dissolved Solids
Region 6     
Squaw Creek
 
LOE ID: 26288
 
Pollutant: Total Dissolved Solids
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: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. TDS concentrations were 29, 38, and 44 mg/L. The mean concentration for this month was 37 mg/L The water quality objective was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for Total Dissolved Solids (TDS), from Lahontan Basin Plan Table 3-11, is 85 mg/L as a mean of monthly means for the period of record.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 75845, Total Dissolved Solids
Region 6     
Squaw Creek
 
LOE ID: 133447
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan SWAMP staff for routine regional monitoring at one location in 2014 and 2015. Concentrations in the raw data ranged from 57 to 214 mg/L. Two annual averages can be computed, one of which exceed the water quality objective for total dissolved solids.
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 Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration not to exceed 85.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected at one location, 635SQLB01, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in September and October 2014 and in January, April, September and December 2015.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 75845, Total Dissolved Solids
Region 6     
Squaw Creek
 
LOE ID: 26290
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for three samples collected on December 19, 2006 at three different stations in Squaw Creek. TDS concentrations were 29, 38, and 44 mg/L. The MCL was not exceeded.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The recommended MCL for Total Dissolved Solids (TDS) is 500 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Three stations (D-1, D-2 and D-3) were sampled.
Temporal Representation: All three samples were collected on the same date, December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
 
DECISION ID
102131
Region 6     
Squaw 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: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 1 of 6 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 1 of 6 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102131, Total Kjeldahl Nitrogen (TKN)
Region 6     
Squaw Creek
 
LOE ID: 96842
 
Pollutant: Total Kjeldahl Nitrogen (TKN)
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 the Truckee River Watershed Council between May 2011 and September 2016. Concentrations in the raw data ranged from 0.035 to 0.156 mg/L. Six annual averages can be computed, one of which exceed the water quality objective for TKN in 2016 (result=0.156 mg/L).
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Watershed Council.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site specific objective for total kjeldahl nitrogen (TKN) in Squaw Creek, as referenced in the Lahontan Basin Plan Table 3-11, is an annual average concentration 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 at one location, MTRSQCR00, just upstream from the confluence with the Truckee River.
Temporal Representation: Data were collected in in May of 2011, 2012, 2013; in May and September of 2014; in May and June of 2015; and in May and September of 2016.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified. Lahontan staff completed the Squaw Creek sediment TMDL in 2006 and the plan was accepted by USEPA in 2007.
QAPP Information: Data were collected in accordance with the Truckee River Monitoring Plan QAPP.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
 
DECISION ID
102133
Region 6     
Squaw 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 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.

Two lines of evidence are available in the administrative record to assess this pollutant. 0 of 9 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 9 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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102133, Turbidity
Region 6     
Squaw Creek
 
LOE ID: 97423
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Truckee River Watershed Council data for Squaw Creek to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality standard for Turbidity.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Truckee River Watershed Council.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The objective for turbidity in Squaw Creek, as stipulated in the Lahontan Basin Plan Chapter 3-8, is a mean of monthly mean value not to exceed 3 Nephelometric Turbidity Units (NTU).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
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) (MTRSQCR00)
Temporal Representation: The samples were collected between the dates of 2010-09-25 and 2016-09-22
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
Line of Evidence (LOE) for Decision ID 102133, Turbidity
Region 6     
Squaw Creek
 
LOE ID: 97246
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 Squaw Creek to determine beneficial use support and results are as follows: 0 of 2 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: The objective for turbidity in Squaw Creek, as stipulated in the Lahontan Basin Plan Chapter 3-8, is a mean of monthly mean value not to exceed 3 Nephelometric Turbidity Units (NTU).
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
 
DECISION ID
102134
Region 6     
Squaw Creek
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant. pH evaluations require information regarding background water quality conditions in the waterbody in order to assess changes to pH conditions in the waterbody. This background information was not available for this assessment and the computed sample size is therefore zero. 0 of 0 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 satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 0 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 3.1.
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 Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 102134, pH
Region 6     
Squaw Creek
 
LOE ID: 129710
 
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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102134, pH
Region 6     
Squaw Creek
 
LOE ID: 129551
 
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 Truckee River Watershed Council.
 
SWAMP Data: Non-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) (MTRSQCR00)
Temporal Representation: The samples were collected between the dates of 2010-09-25 and 2016-09-22
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
Line of Evidence (LOE) for Decision ID 102134, pH
Region 6     
Squaw Creek
 
LOE ID: 129739
 
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 Truckee River Watershed Council.
 
SWAMP Data: Non-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) (MTRSQCR00)
Temporal Representation: The samples were collected between the dates of 2010-09-25 and 2016-09-22
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
QAPP Information Reference(s): Quality Assurance Project Plan (QAPP) for Truckee River Monitoring Plan.
 
Line of Evidence (LOE) for Decision ID 102134, pH
Region 6     
Squaw Creek
 
LOE ID: 129683
 
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 Truckee River Water Quality Monitoring Plan.
 
SWAMP Data: Non-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 3 monitoring site(s) (BIO-SC1, BIO-SC2, BIO-SC3)
Temporal Representation: The samples were collected between the dates of 2012-07-23 and 2014-06-27
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Water Quality Monitoring Plan
QAPP Information Reference(s): Sampling and Analysis Plan for Implementation of the Truckee River Water Quality Monitoring Plan Water Year 2014
 
Line of Evidence (LOE) for Decision ID 102134, pH
Region 6     
Squaw Creek
 
LOE ID: 129789
 
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) (635SQLB01)
Temporal Representation: The samples were collected between the dates of 2014-09-23 and 2015-12-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program
 
Line of Evidence (LOE) for Decision ID 102134, pH
Region 6     
Squaw Creek
 
LOE ID: 129685
 
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 Truckee River Water Quality Monitoring Plan.
 
SWAMP Data: Non-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 3 monitoring site(s) (BIO-SC1, BIO-SC2, BIO-SC3)
Temporal Representation: The samples were collected between the dates of 2012-07-23 and 2014-06-27
Environmental Conditions:
QAPP Information: Quality Assurance Project Plan (QAPP) for Truckee River Water Quality Monitoring Plan
QAPP Information Reference(s): Sampling and Analysis Plan for Implementation of the Truckee River Water Quality Monitoring Plan Water Year 2014
 
 
DECISION ID
69734
Region 6     
Squaw Creek
 
Pollutant: Iron
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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.

Two lines of evidence are available in the administrative record to assess this pollutant. The single sample does not exceed California Maximum Contaminant Level (MCL) or the site-specific 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 satisfies 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 or Table 3.1 of the Policy.
3. The single sample did not exceed the MCL or the site specific 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 Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 69734, Iron
Region 6     
Squaw Creek
 
LOE ID: 26282
 
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: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for one sample collected at Station D-3 in Squaw Creek. The iron concentration was 116 ug/L. The objective was not violated.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The site-specific objective for iron, from Lahontan Basin Plan Table 3-11, is 0.13 mg/L ( equal to 130 ug/L) as a mean of monthly means for the period of record.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Iron was determined for one sample from Station D-3.
Temporal Representation: One sample was collected on December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 69734, Iron
Region 6     
Squaw Creek
 
LOE ID: 26283
 
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: Not Specified
Data Used to Assess Water Quality: The Squaw Valley Public Service District (a drinking water purveyor) submitted laboratory results for one sample collected at Station D-3 in Squaw Creek. The iron concentration was 116 ug/L. The MCL was not violated.
Data Reference: 2007. Chemical Report dated 01/08/07 on samples collected from Squaw Creek on 12/19/06 by the Squaw Valley Public Service District
 
SWAMP Data: Non-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 iron is 300 ug/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Iron was determined for one sample from Station D-3.
Temporal Representation: One sample was collected on December 19, 2006.
Environmental Conditions: Squaw Creek is a tributary of the Truckee River downstream of Lake Tahoe. Its watershed includes residential, commercial and recreational (ski resort and golf course) development. Part of the creek channel has been hydromodified.
QAPP Information: The data were analyzed by Cranmer Analytical Laboratory, a California state certified laboratory. Some quality assurance information was provided with the data.
QAPP Information Reference(s):
 
 
DECISION ID
71560
Region 6     
Squaw Creek
 
Pollutant: Sedimentation/Siltation
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Original
Sources: Construction/Land Development | Drainage/Filling Of Wetlands | Highway Maintenance and Runoff | Hydromodification | Natural Sources | Nonpoint Source | Other Urban Runoff | Recreational and Tourism Activities (non-boating)
TMDL Name: Squaw Creek Sediment
TMDL Project Code: 186
Date TMDL Approved by USEPA: 07/27/2007
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Regional Board Conclusion:

This pollutant was considered for placement on the section 303d) 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:

303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.
 
Regional Board Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 71560, Sedimentation/Siltation
Region 6     
Squaw Creek
 
LOE ID: 2869
 
Pollutant: Sediment
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: Not Specified
Data Used to Assess Water Quality: The Squaw Creek Sediment TMDL was approved by the RWQCB in 2006 and subsequently approved by USEPA.
Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):