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

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name: Ward Creek
Water Body ID: CAR6342002019980805120910
Water Body Type: River & Stream
 
DECISION ID
79916
Region 6     
Ward Creek
 
Pollutant: Nitrogen
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Revised
Sources: Source Unknown
TMDL Name: Lake Tahoe Nutrients/Sediment
TMDL Project Code: 198
Date TMDL Approved by USEPA: 08/16/2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant was considered for placement on the section 303 (d) list in a previous listing cycle. 303(d) listing decisions made prior to 2006 were not held in an assessment database.

Regional Board conclusion: New information was reviewed for the current (2018) assessment cycle. The previous conclusion has changed to do not delist. Since the 2010 assessment cycle the Lake Tahoe TMDL, which partly addresses the nitrogen impairment within this segment of Ward Creek, was adopted. Ward Creek is a tributary to Lake Tahoe. On-the-ground efforts required by the Lake Tahoe TMDL will also achieve pollutant load reductions in waters tributary to Lake Tahoe, including Ward Creek.

Long-term water quality trends and pollutant load reduction tracking in Ward Creek will be captured through the ongoing efforts of the Lake Tahoe Interagency Monitoring Program (LTIMP) whose primary objective is to monitor discharge, nutrient load, and sediment loads from representative streams that flow into Lake Tahoe. Nitrogen and phosphorus loading calculations are performed using the LTIMP flow and nutrient concentration database. LTIMP has monitored Ward Creek and other tributaries to Lake Tahoe since 1988; this data is stored on the USGS website at http://wdr.water.usgs.gov/.

This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

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 1 samples assessed for the 2018 listing cycle exceeded the water quality objective. Data which is unavailable in the database because it was assessed prior to 2006 exceeds the allowable frequency listed in Table 3.1 of the Listing Policy, and this data is the basis for placing this waterbody on the CWA 303(d) list during previous cycles.
4. The Lake Tahoe TMDL was approved by USEPA on 08-16-2011.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because there is insufficient information to assess whether the applicable water quality standards for the pollutant continue to be exceeded.
 
 
Line of Evidence (LOE) for Decision ID 79916, Nitrogen
Region 6     
Ward Creek
 
LOE ID: 96686
 
Pollutant: Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan field staff collecting data for the Surface Water Ambient Monitoring Program (SWAMP) Reference Condition Management Plan. One data point was collected on one day in September 2013. The concentration was reported as non-detectable with a reporting limit of 0.05mg/L, which attains the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for nitrogen in Ward Creek, as referenced in the Lahontan Basin Plan table 3-12, is an annual average concentration not to exceed 0.15 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 634WRD001, which is located approx. 150ft downstream of the Tahoe Rim Trail Crossing near Courchevel Road.
Temporal Representation: Data were collected on one day in September 2013.
Environmental Conditions: Ward Creek drains the western Tahoe Rim from Ward Peak. The watershed is affected in it's upper northern part by Alpine Meadows ski resort, and residential properties occur throughout the drainage. The lower portions of the creek flow along the northern boundary of the Tahoe State Recreation Area before emptying into Hurricane Bay.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79916, Nitrogen
Region 6     
Ward Creek
 
LOE ID: 4660
 
Pollutant: Nitrogen
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
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: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
79819
Region 6     
Ward Creek
 
Pollutant: Phosphorus
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Revised
Sources: Source Unknown
TMDL Name: Lake Tahoe Nutrients/Sediment
TMDL Project Code: 198
Date TMDL Approved by USEPA: 08/16/2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant was considered for placement on the section 303 (d) list in a previous listing cycle. 303(d) listing decisions made prior to 2006 were not held in an assessment database.

Regional Board conclusion: New information was reviewed for this current (2018) assessment cycle. The previous conclusion has changed since the Lake Tahoe TMDL, which partly addresses the phosphorus impairment within this segment of Ward Creek, was adopted after the 2010 Integrated Report.

Ward Creek is tributary to Lake Tahoe. On-the-ground efforts required by the Lake Tahoe TMDL will also achieve pollutant load reductions in waters tributary to Lake Tahoe, including Ward Creek.

The primary source of phosphorus in Lake Tahoe (and Ward Creek) watershed is urban storm water runoff and phosphorus associated with eroding sediment on disturbed undeveloped lands. Tahoe TMDL implementation plan identifies actions resource management agencies, Lake Tahoe municipalities (El Dorado and Placer Counties, and City of South Lake Tahoe) and California Department of Transportation (CalTrans) must take to reduce inputs of nutrients (nitrogen and phosphorus) and fine sediment in urban runoff discharges. On the ground efforts required by the Lake Tahoe TMDL that focus on (1) stabilizing disturbed areas within the forested uplands, (2) restoring eroding stream channels, and (3) managing and treating urban uplands (e.g. street sweeping, installing and maintaining infiltration and stormwater treatment facilities) will also achieve pollutant load reductions in waters tributary to Lake Tahoe.

Long-term water quality trends and pollutant load reduction tracking in Ward Creek will be captured through the ongoing efforts of the Lake Tahoe Interagency Monitoring Program (LTIMP) whose primary objective is to monitor discharge, nutrient load, and sediment loads from representative streams that flow into Lake Tahoe. Nitrogen and phosphorus loading calculations are performed using the LTIMP flow and nutrient concentration database. LTIMP has monitored Ward Creek and other tributaries to Lake Tahoe since 1988; this data is stored on the USGS website at http://wdr.water.usgs.gov/.

This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

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 1 samples assessed during this assessment cycle exceeded the water quality objective; Data which was assessed prior to 2006 and which is not available in the CalWQA database exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. The Lake Tahoe TMDL was approved by USEPA on 08-16-2011.
5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 79819, Phosphorus
Region 6     
Ward Creek
 
LOE ID: 96687
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan field staff collecting data for the Surface Water Ambient Monitoring Program (SWAMP) Reference Condition Management Plan. One data point was collected on one day in September 2013. The concentration was reported as 0.0161 mg/L, which exceeds the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for phosphorous in Ward Creek, as referenced in the Lahontan Basin Plan table 3-12, is an annual average concentration not to exceed 0.015 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 634WRD001, which is located approx. 150ft downstream of the Tahoe Rim Trail Crossing near Courchevel Road.
Temporal Representation: Data were collected on one day in September 2013.
Environmental Conditions: Ward Creek drains the western Tahoe Rim from Ward Peak. The watershed is affected in it's upper northern part by Alpine Meadows ski resort, and residential properties occur throughout the drainage. The lower portions of the creek flow along the northern boundary of the Tahoe State Recreation Area before emptying into Hurricane Bay.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 79819, Phosphorus
Region 6     
Ward Creek
 
LOE ID: 4661
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
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: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
101406
Region 6     
Ward 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 Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. 0 of 4 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 4 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 is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101406, Alkalinity as CaCO3
Region 6     
Ward Creek
 
LOE ID: 97321
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed TRPA Tahoe Ambient Monitoring data for Ward Creek to determine beneficial use support and results are as follows: 0 of 3 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 Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
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 3 monitoring site(s) (634S14235, 634S14259, 634S16303)
Temporal Representation: The samples were collected between the dates of 2014-08-07 and 2016-08-01
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101406, Alkalinity as CaCO3
Region 6     
Ward Creek
 
LOE ID: 98759
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 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 Reference Condition Management Plan (RCMP).
 
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) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101426
Region 6     
Ward Creek
 
Pollutant: Ammonia
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 1 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 1 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 is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101426, Ammonia
Region 6     
Ward Creek
 
LOE ID: 97924
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Ammonia as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
103408
Region 6     
Ward 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 Staff 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, one evaluating benthic-macroinvertebrate bioassessment data and one evaluating habitat assessment data, are available in the administrative record to assess this indicator. 1 of 6 bioassessment samples exceed the California Stream Condition Index (CSCI) impairment threshold. 0 of 2 habitat assessment samples exceed the Index of Physical Habitat Integrity (IPI) impairment threshold. 1 of 6 benthic-macroinvertebrate samples exceed the CSCI threshold which does not exceed the impairment frequency stipulated in section 3.9 of the listing policy 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 6 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. Additionally, 0 of 2 habit assessment samples had IPI scores below 0.83. 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 Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 103408, Benthic Community Effects
Region 6     
Ward Creek
 
LOE ID: 96463
 
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: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: There were two CSCI scores for this site. One score was 0.56075505 and then there were two samples that were taken the same day from a different site and averaged for a score of 0.969598104. One of the two scores is exceeding the water quality objective for the aquatic life beneficial use.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
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: The California Stream Condition Index (CSCI): A New Statewide Biological Scoring Tool for Assessing the Health of Freshwater Streams.
 
Spatial Representation: Samples collected at the following station: 634S14235
Temporal Representation: Sample was collected on 8/7/2014
Environmental Conditions:
QAPP Information: QAPP for TRPA Tahoe Ambient Monitoring
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 103408, Benthic Community Effects
Region 6     
Ward Creek
 
LOE ID: 96440
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: The site had CSCI scores of 1.065824, 1.267671, 0.802813256 and 1.152170491. Therefore, this site is not exceeding the water quality objective for the aquatic life beneficial use. 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 Reference Condition Management Plan (RCMP).
 
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: The California Stream Condition Index (CSCI): A New Statewide Biological Scoring Tool for Assessing the Health of Freshwater Streams.
 
Spatial Representation: Samples collected at the following stations: 634WRD001 and 634WRD029
Temporal Representation: Samples Collected on 7/21/2006, 8/18/2005, 9/9/2013 and 6/1/2015.
Environmental Conditions:
QAPP Information: QAPP for SWAMP Reference Condition Management Plan.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 103408, Benthic Community Effects
Region 6     
Ward Creek
 
LOE ID: 132779
 
Pollutant: Habitat Assessment (Streams)
LOE Subgroup: Ancillary Line of Evidence
Matrix: -N/A
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: HABITAT ASSESSMENT
Data Used to Assess Water Quality: The site had an IPI score of
0.84
0.89
These scores indicate that the site is possibly altered.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
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: Physical characteristics of a site vary due to both natural factors and human disturbance. Statistical models based on a large statewide reference data set can help distinguish natural variability from anthropogenic stress. These models work across the diverse stream types found in California. The Index of Physical Habitat Integrity (IPI) is a multimetric Index developed based on these models to characterize physical habitat condition for streams in California. Index scores near 1 indicate physical habitat conditions similar to reference, whereas lower scores indicate degradation. For the purposes of making statewide assessments, three thresholds (analogous to those used for the CSCI) were established based on the 30th; 10th; and 1st percentiles of IPI scores at reference sites. These three thresholds divide the IPI scoring range into 4 categories of physical condition as follows: greater than or equal to 0.94 = likely intact condition; 0.93 to 0.84 = possibly altered condition; 0.83 to 0.71 = likely altered condition; less than or equal to 0.70 = very likely altered condition. Scores of 0.83 lower indicate that the physical habitat has been altered and low CSCI scores from this site may be due to impacts to the physical habitat.
Guideline Reference: An Index to Measure the Quality of Physical Habitat in California Wadeable Streams
 
Spatial Representation: Samples collected at the following stations: 634WRD001 and 634WRD029
Temporal Representation: Samples Collected on 9/9/2013 and 6/1/2015.
Environmental Conditions:
QAPP Information: QAPP for SWAMP Reference Condition Management Plan.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101407
Region 6     
Ward Creek
 
Pollutant: Chloride
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 1 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 1 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 is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101407, Chloride
Region 6     
Ward Creek
 
LOE ID: 96685
 
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: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan field staff collecting data for the Surface Water Ambient Monitoring Program (SWAMP) Reference Condition Management Plan. One data point was collected on one day in September 2013. The concentration was reported as 0.25 mg/L, which attains the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for chloride in Ward Creek, as referenced in the Lahontan Basin Plan table 3-12, is an annual average concentration not to exceed 0.3 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 634WRD001, which is located approx. 150ft downstream of the Tahoe Rim Trail Crossing near Courchevel Road.
Temporal Representation: Data were collected on one day in September 2013.
Environmental Conditions: Ward Creek drains the western Tahoe Rim from Ward Peak. The watershed is affected in it's upper northern part by Alpine Meadows ski resort, and residential properties occur throughout the drainage. The lower portions of the creek flow along the northern boundary of the Tahoe State Recreation Area before emptying into Hurricane Bay.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101408
Region 6     
Ward 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 Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. One line of evidence is available to assess E. coli data against the REC-1 beneficial use; Two lines of evidence are available to asses fecal coliform data against the MUN beneficial use. 0 of 1 samples exceed the water quality objective for the REC-1 beneficial use assessment; 1 of 5 samples exceed the objective for the MUN 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 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 1 samples exceed the water quality objective for the REC-1 beneficial use assessment; 1 of 5 samples exceed the objective for the MUN beneficial use assessment and these sample sizes are insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples per beneficial use assessed are needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101408, Indicator Bacteria
Region 6     
Ward Creek
 
LOE ID: 129155
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
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 Ward Creek to determine beneficial use support and the results are as follows: 0 of the 2 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): 634WRDB10
Temporal Representation: The samples were collected between the days of 2014-06-10 and 2014-10-20 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101408, Indicator Bacteria
Region 6     
Ward Creek
 
LOE ID: 129333
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB6_BACT_Monitoring data for Ward Creek to determine beneficial use support and the results are as follows: 1 of the 3 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): 634WRDB10
Temporal Representation: The samples were collected between the days of 2014-06-10 and 2014-10-20 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101408, Indicator Bacteria
Region 6     
Ward Creek
 
LOE ID: 99966
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1
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 Ward Creek to determine beneficial use support and the results are as follows: 0 of the 1 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): 634WRDB10
Temporal Representation: The samples were collected between the days of 2014-10-03 and 2014-10-20 .
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101424
Region 6     
Ward 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 Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 1 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 1 samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101424, Nitrate/Nitrite (Nitrite + Nitrate as N)
Region 6     
Ward Creek
 
LOE ID: 97806
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Nitrate + Nitrite as N.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
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) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101429
Region 6     
Ward 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 Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Three lines of evidence, two which assess the available dissolved oxygen data and one which assesses the available dissolved oxygen saturation data are available in the administrative record to assess this pollutant. 0 of 4 dissolved oxygen samples exceed the water quality objective; 0 of 1 dissolved oxygen saturation samples exceeds 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy.
3. 0 of 4 dissolved oxygen samples exceed the water quality objective; 0 of 1 dissolved oxygen saturation samples exceeds 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 per fraction assessed are needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101429, Oxygen, Dissolved
Region 6     
Ward Creek
 
LOE ID: 129958
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed TRPA Tahoe Ambient Monitoring data for Ward Creek to determine beneficial use support and results are as follows: 0 of 3 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 Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: For waters with the beneficial uses of COLD, COLD with SPWN, WARM, and WARM with SPWN, the minimum dissolved oxygen concentration shall not be less than that specified in Table 3-6. (Water Quality Control Plan, Lahontan Region)
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 3 monitoring site(s) (634S14235, 634S14259, 634S16303)
Temporal Representation: The samples were collected between the dates of 2014-08-07 and 2016-08-01
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101429, Oxygen, Dissolved
Region 6     
Ward Creek
 
LOE ID: 130075
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for Oxygen, Dissolved.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: For waters with the beneficial uses of COLD, COLD with SPWN, WARM, and WARM with SPWN, the minimum dissolved oxygen concentration shall not be less than that specified in Table 3-6. (Water Quality Control Plan, Lahontan Region)
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101429, Oxygen, Dissolved
Region 6     
Ward Creek
 
LOE ID: 130058
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed TRPA Tahoe Ambient Monitoring data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 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 Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan for the Lahontan Region's water quality objective states that the dissolved oxygen concentration shall not be less than 80 percent of saturation.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (634S16303)
Temporal Representation: The samples were collected between the dates of 2016-08-01 and 2016-08-01
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101431
Region 6     
Ward 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 Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. 0 of 4 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 4 samples exceeded the objective and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 26 samples are needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101431, Specific Conductivity
Region 6     
Ward Creek
 
LOE ID: 97867
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 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 Reference Condition Management Plan (RCMP).
 
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) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101431, Specific Conductivity
Region 6     
Ward Creek
 
LOE ID: 97343
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed TRPA Tahoe Ambient Monitoring data for Ward Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceeded the water quality standard for SpecificConductivity.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
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 3 monitoring site(s) (634S14235, 634S14259, 634S16303)
Temporal Representation: The samples were collected between the dates of 2014-08-07 and 2016-08-01
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101433
Region 6     
Ward Creek
 
Pollutant: Sulfates
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. 0 of 1 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 1 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 is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101433, Sulfates
Region 6     
Ward Creek
 
LOE ID: 96688
 
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by Lahontan field staff collecting data for the Surface Water Ambient Monitoring Program (SWAMP) Reference Condition Management Plan. One data point was collected on one day in September 2013. The concentration was reported as 0.86 mg/L, which attains the site specific objective.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the SWAMP Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The site specific objective for sulfates in Ward Creek, as referenced in the Lahontan Basin Plan table 3-12, is an annual average concentration not to exceed 1.4 mg/L.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data were collected from one site, 634WRD001, which is located approx. 150ft downstream of the Tahoe Rim Trail Crossing near Courchevel Road.
Temporal Representation: Data were collected on one day in September 2013.
Environmental Conditions: Ward Creek drains the western Tahoe Rim from Ward Peak. The watershed is affected in it's upper northern part by Alpine Meadows ski resort, and residential properties occur throughout the drainage. The lower portions of the creek flow along the northern boundary of the Tahoe State Recreation Area before emptying into Hurricane Bay.
QAPP Information: Data were collected in accordance with the SWAMP QAPP.
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
101436
Region 6     
Ward 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 Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Assessment of the water quality objectives for pH, as stipulated in the Lahontan Basin Plan Chapter 3, require background information regarding water quality conditions in the waterbody. This background information was not available for this assessment, and therefore the computed sample size is 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 is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to SECTION 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
 
Line of Evidence (LOE) for Decision ID 101436, pH
Region 6     
Ward Creek
 
LOE ID: 129770
 
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 Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
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 3 monitoring site(s) (634S14235, 634S14259, 634S16303)
Temporal Representation: The samples were collected between the dates of 2014-08-07 and 2016-08-01
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101436, pH
Region 6     
Ward Creek
 
LOE ID: 129788
 
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 Reference Condition Management Plan (RCMP).
 
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) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101436, pH
Region 6     
Ward Creek
 
LOE ID: 129612
 
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 Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.
 
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 3 monitoring site(s) (634S14235, 634S14259, 634S16303)
Temporal Representation: The samples were collected between the dates of 2014-08-07 and 2016-08-01
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101436, pH
Region 6     
Ward Creek
 
LOE ID: 129669
 
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 Reference Condition Management Plan (RCMP).
 
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) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
 
DECISION ID
70096
Region 6     
Ward Creek
 
Pollutant: Iron
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2031
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: Regional Board Conclusion:

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

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

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 Staff Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
 
Line of Evidence (LOE) for Decision ID 70096, Iron
Region 6     
Ward Creek
 
LOE ID: 4659
 
Pollutant: Iron
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
101435
Region 6     
Ward Creek
 
Pollutant: Turbidity
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Source Unknown
TMDL Name: Lake Tahoe Nutrients/Sediment
TMDL Project Code: 198
Date TMDL Approved by USEPA: 08/16/2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. 7 of 30 samples exceed the water quality objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the 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. 7 of 30 samples exceed the objective and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Staff Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
 
Line of Evidence (LOE) for Decision ID 101435, Turbidity
Region 6     
Ward Creek
 
LOE ID: 97002
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Reference Condition Management Plan data for Ward Creek to determine beneficial use support and results are as follows: 0 of 1 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 Reference Condition Management Plan (RCMP).
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water designated as MUN shall not contain concentrations of chemical constituents in excess of the maximum contaminant level (MCL) or secondary maximum contaminant level (SMCL) based upon drinking water standards specified in Title 22 of the California Code of Regulations. The Lahontan Basin Plan also has regionwide turbidity objective for other beneficial uses that states: Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10%.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient surface waters under the Lahontan Basin Plan's \Chemical Constituents\" objective. The Secondary MCL for turbidity is 5 NTU. Calculation of a numeric objective for other beneficial uses requires comparison with upstream or other background data which may not be available as part of the data used for water quality assessment. "
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (634WRD001)
Temporal Representation: The samples were collected between the dates of 2013-09-09 and 2013-09-09
Environmental Conditions:
QAPP Information: Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
QAPP Information Reference(s): Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program
 
Line of Evidence (LOE) for Decision ID 101435, Turbidity
Region 6     
Ward Creek
 
LOE ID: 98968
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 29
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed NWIS data for Ward Creek to determine beneficial use support and results are as follows: 7 of 29 samples exceeded the water quality standard for Turbidity.
Data Reference: Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for the USGS National Water Information System.
 
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. The Lahontan Basin Plan also has regionwide turbidity objective for other beneficial uses that states: Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10%.
Objective/Criterion Reference: Water Quality Control Plan for the Lahontan Region (as amended)
 
Evaluation Guideline: California Maximum Contaminant Levels (MCLs) apply to ambient surface waters under the Lahontan Basin Plan's \Chemical Constituents\" objective. The Secondary MCL for turbidity is 5 NTU. Calculation of a numeric objective for other beneficial uses requires comparison with upstream or other background data which may not be available as part of the data used for water quality assessment. "
Guideline Reference: California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring
 
Spatial Representation: The samples were collected at 1 monitoring site(s) (USGS-10336676)
Temporal Representation: The samples were collected between the dates of 2014-10-20 and 2016-09-16
Environmental Conditions:
QAPP Information: QAPP not required for federal data
QAPP Information Reference(s): This is a placeholder reference for data which does not require a QAPP.
 
 
DECISION ID
79663
Region 6     
Ward 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: Channel Erosion
TMDL Name: Lake Tahoe Nutrients/Sediment
TMDL Project Code: 198
Date TMDL Approved by USEPA: 08/16/2011
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Staff Conclusion: This pollutant was considered for placement on the section 303 (d) list in a previous listing cycle. 303(d) listing decisions made prior to 2006 were not held in an assessment database.

Regional Board conclusion: No new data were assessed for this assessment cycle, however; the final listing decision has changed since the Lake Tahoe TMDL, which partly addresses the sediment impairment within Ward Creek, was adopted after the 2010 Integrated Report.

Ward Creek is a tributary to Lake Tahoe. On-the-ground efforts required by the Lake Tahoe TMDL will also achieve pollutant load reductions in waters tributary to Lake Tahoe, including Ward Creek.

The primary source of fine sediment particles in the Lake Tahoe (and Ward Creek) watershed is urban storm water runoff and eroding sediment on disturbed undeveloped lands. The Tahoe TMDL implementation plan identifies actions that resource management agencies, Lake Tahoe municipalities (El Dorado and Placer Counties, and the City of South Lake Tahoe) and California Department of Transportation (CalTrans) must take to reduce inputs of nutrients (nitrogen and phosphorus) and fine sediment in urban runoff discharges. On the ground efforts required by the Lake Tahoe TMDL that focus on (1) stabilizing disturbed areas within the forested uplands, (2) restoring eroding stream channels, and (3) managing and treating urban uplands (e.g. street sweeping, installing and maintaining infiltration and stormwater treatment facilities) will also achieve pollutant load reductions in waters tributary to Lake Tahoe.

Pollutant loads from urban uplands within the Ward Creek watershed are being address by the Lake Tahoe TMDL. Municipal Stormwater NPDES permits require the Lake Tahoe municipalities and CalTrans to develop and implement comprehensive pollutant load reduction programs (PLRPs) to meet specified pollutant load reduction requirements. Expected implementation measures include a variety of alternative treatment options, roadway operation practices, and local ordinances to reduce average annual pollutant loads. These Lake Tahoe TMDL implementation efforts will also reduce inputs ofsediment to this impaired segment of Ward Creek.

Maintenance activities and restoring small disturbed sites that are underway, or planned and expected, within the forested uplands of this watershed will also reduce or avoid increases in fine sediment and nutrient loads.

Additionally, the Lake Tahoe TMDL also requires implementation of measures to control stationary sources of dust which help reduce pollutant loads of fine sediments. Implementation of these measures helps address the phosphorus loading that impairs Ward Creek that is associated with these fine sediments from dust sources.
Federal, State, and larger local restoration agencies have well defined multi objective restoration programs with established funding and developed restoration plans, which will help reduce the sediment loads that impact the Ward Creek.

Implementation of the California Department of Parks and Recreation 2011 Ward Creek Roads and Trails Sediment Reduction Project (WDID No. 6A311008004) has and continues to reduce inputs of fine sediments to Ward Creek associated with the trail system within the Ward Creek watershed. The Project has reduced impacts of the trail system on the wet meadow, lower Ward Creek watershed, and Lake Tahoe by a combination of improving drainage and re-routing and re-contouring trails, restoring old road beds, and de-compacting abandoned trails. Restored wet meadow areas received permanent structures to divert runoff and mulch cover to provide erosion control and a seed source.

Finally, the Lake Tahoe TMDL also requires implementation of measures to control stationary sources of dust and organic soot which help reduce pollutant loads of fine sediments. Implementation of these measures helps address the phosphorus loading (associated with these fine sediments from dust sources) that impairs Ward Creek.

Pollutant load reductions within Ward Creek will be tracked through implementation of detailed performance and compliance measures and assessment and reporting protocols included in the Lake Tahoe TMDL. The TMDL Management System project is establishing activity-based tracking and reporting requirements to assess activities that are expected to reduce pollutant loading from non-urban sources.

The Lahontan Water Board and the Nevada Division of Environmental Protection will implement a Lake Tahoe TMDL Management System for managing, tracking, integrating and evaluating new information generated from TMDL implementation actions, effectiveness monitoring, research efforts, and other factors such as climate change and wildfires.

The Management System is based on an adaptive management framework to (1) link load reduction effectiveness with project implementation monitoring to improve project design and to assess if actual environmental improvement is occurring as expected; (2) establish guidance and operation protocols for how new information will be incorporated into project designs and TMDL program implementation; (3) establish prioritized TMDL research needs to fill data gaps and reduce uncertainties, and (4) implement a process for updating and reporting pollutant load reduction estimates and tracking projects within the TMDL implementation timeline.

The Lake Tahoe TMDL requires implementation, effectiveness, and status and trends monitoring. Tributary stream status and trends monitoring will track long-term changes in water quality conditions relative to established water quality standards or goals, and project-specific monitoring will be used to assess the efficacy of various implementation measures.

Long-term water quality trends and pollutant load reduction tracking in Ward Creek will be captured through the ongoing efforts of the Lake Tahoe Interagency Monitoring Program (LTIMP) whose primary objective is to monitor discharge, nutrient load, and sediment loads from representative streams that flow into Lake Tahoe. LTIMP has monitored Ward Creek and other tributaries to Lake Tahoe since 1988; this data is stored on the USGS website at http://wdr.water.usgs.gov/.
 
Regional Board Staff Decision Recommendation: This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.
 
 
Line of Evidence (LOE) for Decision ID 79663, Sedimentation/Siltation
Region 6     
Ward Creek
 
LOE ID: 4662
 
Pollutant: Sedimentation/Siltation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
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: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):