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

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name:	Cold Creek
Water Body ID:	CAR6341003020000207114402
Water Body Type:	River & Stream


DECISION ID	76221	Region 6
Cold Creek

Pollutant:	Nitrogen
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (being addressed by action other than TMDL)(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: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Three annual average datapoints at a station downstream of a proposed watershed restoration site exceed the water quality objective. One annual average datapoint exceeds the objective at an upstream station. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. One out of three datapoints at an upstream site exceeds the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. Three out of three datapoints at a downstream site exceed the objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board 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 76221, Nitrogen	Region 6
Cold Creek

LOE ID:

26273

Pollutant:

Total Nitrogen as N

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled total Kjeldahl nitrogen (TKN) and nitrate plus nitrate at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, and 2005. Total nitrogen was calculated for sampling dates when both TKN and nitrite plus nitrate data were available. Annual averages for the "above" station were 0.183, 0.182 and 0.207 mg/L. Annual averages for the "below" station were 0.206, 0.249 and 0.287 mg/L. The objective was exceeded at the "below" station in 3 out of 3 years.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The site-specific water quality objective for total nitrogen in Trout Creek applies upstream to Cold Creek through the tributary rule. The objective (from Lahontan Basin Plan Table 5.1-3) is an annual average of 0.19 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Total Kjeldahl nitrogen and nitrite plus nitrate were sampled at approximately weekly intervals between March and September in 2003, 2004 and 2005, with 20 to 22 samples per station per year. Additional sampling was done in October and November 2005. One duplicate sample was reported for the "below"station in 2005.

Environmental Conditions:

Cold Creek is tributary to Trout Creek. Trout Creek joins the Upper Truckee River near Lake Tahoe. In 2003, the LTBMU acquired 1790 acres of private land in the upper Cold Creek watershed, in an area known as "High Meadows." The elevation is about 7800 feet. The creek channel in this area became incised, and the wet meadow dried and was invaded by lodgepole pine, due to the effects of livestock grazing and diversions for pasture irrigation. The LTBMU is planning to restore the stream channel and increase water supply to the meadow in order to restore ecosystem functions.

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):


DECISION ID	101898	Region 6
Cold 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. One line of evidence is available in the administrative record to assess this pollutant. Zero of the one samples exceed the guideline for alkalinity. 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. Zero of one samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 101898, Alkalinity as CaCO3	Region 6
Cold Creek

LOE ID:

97831

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Cold 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:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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	101948	Region 6
Cold 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. Zero of the nine samples exceed the criteria for Total Ammonia as N.. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one samples exceeded the criteria and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 101948, Ammonia	Region 6
Cold Creek

LOE ID:

97886

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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	103515	Region 6
Cold 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. 0 of 2 benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. 0 of 1 habitat assessment samples exceed the Index of Physical Habitat Integrity (IPI) impairment threshold. Both lines of evidence achieve the CSCI and IPI thresholds indicating that the waterbody is likely unimpaired for Benthic Community Effects 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. 0 of 2 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 1 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 103515, Benthic Community Effects	Region 6
Cold Creek

LOE ID:

132767

Pollutant:

Habitat Assessment (Streams)

LOE Subgroup:

Ancillary Line of Evidence

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

HABITAT ASSESSMENT

Data Used to Assess Water Quality:

The site had an IPI score of 0.97 and this score indicates that the habitat is likely intact at this site.

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 or 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:

Sample collected at the following station: 634CLD001

Temporal Representation:

Sample Collected on 9/9/2014

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 103515, Benthic Community Effects	Region 6
Cold Creek

LOE ID:

96406

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The site had CSCI scores of 1.100063925 and 0.965428 and is therefore 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:

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:

Sample collected at the following station: 634CLD001

Temporal Representation:

Sample Collected on 9/9/2014 and 8/23/2001

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	101899	Region 6
Cold 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. Zero of one samples exceed the MUN guideline for chloride. 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. Zero of one samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 101899, Chloride	Region 6
Cold Creek

LOE ID:

97010

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Lahontan Region for chloride is 250 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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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	76605	Region 6
Cold Creek

Pollutant:	Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 127 samples exceed the MUN guideline for nitrate/nitrite as N. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 127 samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 76605, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 6
Cold Creek

LOE ID:

26270

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

126

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled nitrite plus nitrate at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, and 2005. Concentrations in 63 samples from the "above" station ranged from .0.001 to 0.078 mg/L. Concentrations in 63 samples from the "below" station ranged from 0.001 to 0.071 mg/L. The MCL was not exceeded.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for nitrite plus nitrate is 10 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Samples were collected at approximately weekly intervals between March and September, with 20-22 samples per station per year. Additional sampling was done in October and November 2005. A few duplicate samples were collected; these are not included in the sample count

Environmental Conditions:

Cold Creek is tributary to Trout Creek. Trout Creek joins the Upper Truckee River near Lake Tahoe. In 2003 the LTBMU acquired 1790 acres of private land in the upper Cold Creek watershed, in an area known as "High Meadows." The elevation is about 7800 feet. The creek channel in this area became incised, and the wet meadow dried and was invaded by lodgepole pine, due to the effects of livestock grazing and diversions for pasture irrigation. The LTBMU is planning to restore the stream channel and increase water supply to the meadow in order to restore ecosystem functions.

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76605, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 6
Cold Creek

LOE ID:

97022

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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	103238	Region 6
Cold 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, one evaluating dissolved oxygen saturation data and two evaluating dissolved oxygen data are available in the administrative record to assess this pollutant. 1 of 1 dissolved oxygen saturation samples and 0 of 2 dissolved oxygen samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. 1 of 1 dissolved oxygen saturation samples and 0 of 2 dissolved oxygen 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 per pollutant 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 103238, Oxygen, Dissolved	Region 6
Cold Creek

LOE ID:

129978

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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 103238, Oxygen, Dissolved	Region 6
Cold Creek

LOE ID:

130121

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed TRPA Tahoe Ambient Monitoring data for Cold 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 Tahoe Regional Planning Agency (TRPA) Tahoe Ambient Monitoring program.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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) (634S16302)

Temporal Representation:

The samples were collected between the dates of 2016-09-15 and 2016-09-15

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 103238, Oxygen, Dissolved	Region 6
Cold Creek

LOE ID:

130057

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed TRPA Tahoe Ambient Monitoring data for Cold Creek to determine beneficial use support and results are as follows: 1 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) (634S16302)

Temporal Representation:

The samples were collected between the dates of 2016-09-15 and 2016-09-15

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	76265	Region 6
Cold Creek

Pollutant:	Specific Conductivity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the 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. Zero of the 184 samples exceed the MUN guideline for specific conductance. 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. Zero of 184 samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 76265, Specific Conductivity	Region 6
Cold Creek

LOE ID:

6564

Pollutant:

Specific Conductance

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

182

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled two stations above and below a proposed restoration project at approximately weekly intervals between March and September in 2003, 2004, 2005 and 2006. Limited sampling was done in October and November 2005. At the upper station, specific conductance in 90 samples ranged from 5.4 to 26 uS/cm. At the lower station, specific conductance in 92 samples ranged from 3.8 to 60 uS/cm. The MCL was not violated.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for specific conductance is 900 microsiemens per centimeter (uS/cm).

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Specific conductance was measured at approximately weekly intervals between March and September in 2003, 2004, 2005 and 2006. Additonal sampling was done in October and November 2005. A few duplicate samples were collected; they are not included in the totals cited above. .

Environmental Conditions:

Cold Creek is tributary to Trout Creek. Trout Creek joins the Upper Truckee River near Lake Tahoe. In 2003 the LTBMU acquired 1790 acres of private land in the upper Cold Creek watershed, in an area known as "High Meadows" .The elevation is about 7800 feet. The creek channel in this area became incised, and the wet meadow dried and was invaded by lodgepole pine, due to the effects of livestock grazing and diversions for pasture irrigation. The LTBMU is planning to restore the stream channel and increase water supply to the meadow in order to restore ecosystem functions.

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76265, Specific Conductivity	Region 6
Cold Creek

LOE ID:

97352

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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) (634S16302)

Temporal Representation:

The samples were collected between the dates of 2016-09-15 and 2016-09-15

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 76265, Specific Conductivity	Region 6
Cold Creek

LOE ID:

98104

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

California Code of Regulations, Title 22, Division 4, Chapter 15. Domestic Water Quality and Monitoring

Spatial Representation:

The samples were collected at 1 monitoring site(s) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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	101900	Region 6
Cold 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. Zero of one samples exceed the MUN guideline for sulfate. 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. Zero of one samples exceeded the guideline and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 101900, Sulfates	Region 6
Cold Creek

LOE ID:

98062

Pollutant:

Sulfates

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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 Secondary MCL that is incorporated by reference in the Water Quality Control Plan, Lahontan Region for Sulfate 250 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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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	76218	Region 6
Cold Creek

Pollutant:	Turbidity
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant, two of which are based on the same data assessed against the MUN and COLD beneficial use. Eighteen of the 182 samples exceed the MUN guideline for turbidity. The Basin Plan turbidity objective for COLD cannot be assessed since it requires background turbidity data that is not available. 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. Eighteen of 182 samples exceeded the guideline for turbidity and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 76218, Turbidity	Region 6
Cold Creek

LOE ID:

26267

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

181

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Lahontan Basin Plan's regionwide turbidity objective 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 percent."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Turbidity was measured at approximately weekly intervals between March and September in each of four year, with 20-26 samples per station per year. Additional samples were collected in October and November 2005. A few duplicate samples were collected; these are not included in the sample count.

Environmental Conditions:

Cold Creek is tributary to Trout Creek. Trout Creek joins the Upper Truckee River near Lake Tahoe. In 2003 the LTBMU acquired 1790 acres of private land in the upper Cold Creek watershed, in an area known as "High Meadows" The elevation is about 7800 feet. The creek channel in this area became incised, and the wet meadow dried and was invaded by lodgepole pine, due to the effects of livestock grazing and diversions for pasture irrigation. The LTBMU is planning to restore the stream channel and increase water supply to the meadow in order to restore ecosystem functions.

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76218, Turbidity	Region 6
Cold Creek

LOE ID:

97877

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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 76218, Turbidity	Region 6
Cold Creek

LOE ID:

26268

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

181

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled turbidity at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, 2005 and 2006. Turbidity levels in 90 samples from the "above" station ranged from 0.070 to 17.7 NTU. Five of these samples exceeded 5 NTU. Turbidity levels in 91 samples from the "below" station ranged from 0.080 to 22.5 NTU. Thirteen of these samples exceeded 5 NTU. Considering the two stations separately, the MCL was not violated at either station. (Listing Policy section 6.1.5.4 directs that data be aggregated by reach.)

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for turbidity is 5 NTU.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Turbidity was measured at approximately weekly intervals between March and September, with 20-26 samples per station per year. A few duplicate samples were collected; these are not included in the sample count.

Environmental Conditions:

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):


DECISION ID	101949	Region 6
Cold 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 that are based on two data sets each consisting of a single sample. Zero of the zero samples exceed the Basin Plan objective for pH, which requires background data for 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. Zero of zero samples exceeded the objective for pH and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

Line of Evidence (LOE) for Decision ID 101949, pH	Region 6
Cold Creek

LOE ID:

129701

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

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 1 monitoring site(s) (634S16302)

Temporal Representation:

The samples were collected between the dates of 2016-09-15 and 2016-09-15

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 101949, pH	Region 6
Cold Creek

LOE ID:

129648

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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 101949, pH	Region 6
Cold Creek

LOE ID:

129629

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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) (634CLD001)

Temporal Representation:

The samples were collected between the dates of 2014-09-09 and 2014-09-09

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 101949, pH	Region 6
Cold Creek

LOE ID:

129823

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

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:

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) (634S16302)

Temporal Representation:

The samples were collected between the dates of 2016-09-15 and 2016-09-15

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	76641	Region 6
Cold Creek

Pollutant:	Phosphate
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
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 assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence are available in the administrative record to assess this pollutant. No biological data are available to assess compliance with the water quality objective for biostimulatory substances. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. No biological data are available for assessment of compliance with the objective using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76641, Phosphate	Region 6
Cold Creek

LOE ID:

26277

Pollutant:

Phosphate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

122

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled dssolved phosphate at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, and 2005. Results were reported as "SRP/PO4" for 2003 and "SRP/DOP" for 2004 and 2005. These acronyms are assumed to refer to Soluble Reactive Phosphorus and dissolved orthophosphate. SRP is generally considered to be equivalent to orthophosphate. Phosphate concentrations in 122 samples collected over three years ranged from 0.003 to 0.013 mg/L at the "above" station and 0.003 to 0.012 mg/L at the "below" station. No biological data are available for assessment of compliance with the objective for biostimulatory substances.

Forty-one additional samples reported as "DP" were collected in 2003 and 2004. Concentrations ranged from 0.012 to 0.023 at the "above" station and 0.012 to 0.027 at the "below" station.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

There is no applicable site-specific objective for dissolved phosphate. The Lahontan Basin Plan's narrative objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Dissolved phosphate was reported for samples collected at approximately weekly intervals between March and September in 2003, 2004 and 2005, with 18 to 22 samples per station per year. (Additional sampling was done in October and November 2005.)

Environmental Conditions:

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):


DECISION ID	76204	Region 6
Cold Creek

Pollutant:	Phosphorus
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the annual average datapoints exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. None of three annual average datapoints exceeded the site-specific water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	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 76204, Phosphorus	Region 6
Cold Creek

LOE ID:

26276

Pollutant:

Phosphorus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled "Total PO4" at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, and 2005. Annual average concentrations were 0.026, 0.027, and 0.029 mg/L at the "above" station and 0.031, 0.027, and 0.033 mg/L Expressed "as P" rather than "as PO4" (using a conversion factor of 3.08), the annual averages for the "above" station were 0.008, 0.009, and 0.009 mg/L, and the averages for the "below" station were 0.010, 0.009, and 0.011 mg/L. The objective for "total phosphorus" was not exceeded at either station.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The site-specific water quality objective for total phosphorus in Trout Creek applies upstream to Cold Creek through the tributary rule. The objective (from Lahontan Basin Plan Table 5.1-3) is an annual average of 0.015 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

"Total phosphate" was determined for samples collected at approximately weekly intervals between March and September in 2003, 2004 and 2005, with 20 to 22 samples per station per year. Additional sampling was done in October and November 2005.

Environmental Conditions:

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):


DECISION ID	76422	Region 6
Cold Creek

Pollutant:	Sediment
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 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. None of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. None of 130 samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	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 76422, Sediment	Region 6
Cold Creek

LOE ID:

26269

Pollutant:

Sediment

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

126

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled suspended sediment at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, and 2005. Suspended sediment concentrations in 63 samples from the "above" station ranged from 1 to 20.6 mg/L. Flow measurements taken concurrently ranged from 1.43 to 28.755 cubic feet per second (cfs). Three duplicate samples were taken at the "above" station. Suspended sediment concentrations in 63 samples from the "below" station ranged from 2.6 to 34.9 mg/L. Two duplicate samples were taken at the "below" station. The corresponding range of flows was 4.389 to 44.54 cfs. The water quality objective was not exceeded.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The water quality objective for suspended sediment in tributaries of Lake Tahoe is a 90th percentile concentration of 60 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Suspended sediment was sampled at approximately weekly intervals between March and September in 2003, 2004 and 2005, with 21 to 22 samples per station per year. Additional sampling was done in October and November 2005. A few duplicate samples were collected; these are not included in the sample count.

Environmental Conditions:

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):


DECISION ID	76501	Region 6
Cold Creek

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative temperature objective is an antidegradation-based objective that requires that there be no change in temperature in waters designated for the Cold Freshwater Habitat (COLD) beneficial use. The objective does not include specific numerical limits for protection of the COLD use. Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. One line of evidence is available to support this decision. There are not enough temperature samples to establish baseline conditions (including diel, seasonal, annual and interannual variations in temperature) or to detect declining trends in the temperature regime if such trends exist.

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 76501, Temperature, water	Region 6
Cold Creek

LOE ID:

6565

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled temperature at two stations in the upper Cold Creek watershed above and below a proposed restoration project between April and June 2003. Temperatures at the "above" station ranged from 0 to 10 degrees Celsius. Temperatures at the "below" station ranged from 1 to 12 degrees Celsius.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

.The relevant sections of the Lahontan Basin Plan's temperature objective are as follows: "The natural receiving water temperature of all waters shall not be altered unless it can be demonstrated to the satisfaction fo the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses.

For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit ... above or below the natural temperature. For waters designated COLD, the temperature shall not be altered."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Six temperature measurements were taken at each station between April and June 2003.

Environmental Conditions:

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):


DECISION ID	76094	Region 6
Cold Creek

Pollutant:	Total Kjeldahl Nitrogen (TKN)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Staff Conclusion:	This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. No biological data are available for assessment whether any of the chemical samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. No biological data are available for assessment of compliance with the water quality objective and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Staff Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

Line of Evidence (LOE) for Decision ID 76094, Total Kjeldahl Nitrogen (TKN)	Region 6
Cold Creek

LOE ID:

26271

Pollutant:

Total Kjeldahl Nitrogen (TKN)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

121

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

The U.S. Forest Service, Lake Tahoe Basin Management Unit (LTBMU) sampled total Kjeldahl nitrogen (TKN) at two stations in the upper Cold Creek watershed above and below a proposed restoration project in 2003, 2004, and 2005. TKN concentrations in 61 samples from the "above" station ranged from 0.074 to 0.402 mg/L. Concentrations in 60 samples from the "below" station ranged from 0.087 to 1.007 mg/L. No biological data are available for assessment of compliance with the water quality objective.

Data Reference:

2007. Water quality data for upper Cold Creek in the High Meadows Area of the Lake Tahoe Basin

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

There is no site-specific objective for total Kjeldahl nitrogen. The Lahontan Basin Plan's narrative objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."

Objective/Criterion Reference:

Water Quality Control Plan for the Lahontan Region (as amended)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Two stations, above and below a proposed restoration project, were sampled.

Temporal Representation:

Suspended sediment was sampled at approximately weekly intervals between March and September in 2003, 2004 and 2005, with 20 to 21 samples per station per year. Additional sampling was done in October and November 2005.

Environmental Conditions:

QAPP Information:

The LTBMU uses the quality assurance procedures documented in "Water Quality Monitoring Protocols and Sampling Guidelines, LTIMP (Lake Tahoe Interagency Monitoring Program), September 26, 2002.

QAPP Information Reference(s):