Draft California 2026 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name:	Klamath River HU, Lost River HA, Clear Lake, Boles HSAs
Water Body ID:	CAR1059301120011219225345
Water Body Type:	River & Stream


DECISION ID	157139	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Temperature, water
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. For FLETCHER CREEK (LOE 326987), 1 of 1 sample exceeds the cold freshwater habitat beneficial use objective, and this is insufficient data to apply Table 3.2 of the Listing Policy. For WILLOW CREEK (LOE 329260), 1 of 1 sample exceeds the cold freshwater habitat beneficial use objective, and this is insufficient data to apply Table 3.2 of the Listing Policy. For KLAMATH RIVER HU, LOST RIVER HA, CLEAR LAKE, BOLES HSAs, the administrative record indicates that the preservation of rare and endangered species beneficial use is fully supported. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. For FLETCHER CREEK (LOE 326987), 1 of 1 sample exceeds the cold freshwater habitat beneficial use objective, and this is insufficient data to apply Table 3.2 of the Listing Policy; for WILLOW CREEK (LOE 329260), 1 of 1 sample exceeds the cold freshwater habitat beneficial use objective, and this is insufficient data to apply Table 3.2 of the Listing Policy; for KLAMATH RIVER HU, LOST RIVER HA, CLEAR LAKE, BOLES HSAs, the administrative record indicates that the preservation of rare and endangered species beneficial use is fully supported, and this does not exceed the allowable frequency listed in Table 4.2 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 157139, Temperature, water	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

326987

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:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Temperature.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased more than 5 degrees Fahrenheit (F) above natural receiving water temperature (Basin Plan, North Coast Region).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

According to Carter (2008) the lethal temperature evaluation guideline for salmonid spawning, egg incubation & fry emergence is 20C.

Guideline Reference:

Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids. Implications for California's North Coast TMDLs. California Regional Water Quality Control Board, North Coast Region

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157139, Temperature, water	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1662

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Preservation of Rare & Endangered Species

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

The TMDL Analysis was completed for Upper Lost River and Clear Lake Reservoir Watershed. The most sensitive beneficial uses of Clear Lake most likely relate to the protection of the endangered sucker species. The sensitivity analysis using SSTEMP showed that daily average water temperature at the sampling stations in the streams that drain to Clear Lake Reservoir is most sensitive to influence by air temperature, solar radiation, and relative humidity. In the two Upper Lost River stations downstream of Clear Lake Reservoir, water temperature is most sensitive to inflow temperature, that is, the temperature of the water released from the Clear Lake Reservoir. The warmest stream temperatures during the data collection period were found during the week of July 15, 2002. The maximum weekly average temperatures (MWAT) at the sampling stations for that week were: WFLAT, 27.40°C; LRCLDM, 26.64°C; WCGSB, 27.63°C; FCFORD, 22.75°C. These MWATs are well below the Critical Thermal Maxima for Shortnose Suckers (32.1 to 33.3 °C) and also well below the 96-Hour Mean Lethal Concentration for both Long River Suckers and Short Nose Suckers juveniles at 31.2 °C. The water temperature of the watershed supports the most sensitive beneficial use, the endangered sucker species (North Coast RWQCB, 2004d)

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan for the Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan).
Lost River:
1. Cold Interstate Waters: A. Elevated temperature waste discharges into cold interstate waters are prohibited.
2. Warm Interstate Waters: A. Thermal waste discharges having a maximum
temperature greater than 5°F above natural receiving water temperature are prohibited. B. Elevated temperature wastes shall not cause the temperature of warm interstate waters to increase by more than 5°F above natural temperature at any time or place. D. Lost River, Elevated temperature wastes discharged to the Lost River shall not cause the temperature of the receiving water to increase by more than 2°F when the receiving water temperature is less than 62°F, and 0°F when the receiving water temperature exceeds 62°F.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The maximum weekly average temperatures (MWATs) were used from the water body to determine if the Objective was being exceeded. The Lost River Suckers and Shortnose Suckers species are listed under the Endangered Species Act and they are found in the study area. The Critical Thermal Maxima for Shortnose suckers is between the ranges of 32.1 to 33.3 °C (Castleberry and Cech, 1993). The 96-Hour Mean Lethal Concentration (LC50) for Lost River Suckers (LRS) is 31.2 °C for juveniles (with a 95% Confidence Interval range of 30.8 to 31.5 °C for juveniles) and for the Shortnose Suckers (SNS) it is 31.9°C for larva and 31.2 °C for juveniles (with a 95% Confidence Interval range of 30.8 to 31.6 °C for juveniles) (Bellerud and Saiki, 1995) (page 34, TMDL).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

The monitoring locations for the Upper Lost River/Clear Lake Reservoir area are shown in Map 2 and are listed below with their station designations:
1. Lost River below Clear Lake Reservoir dam, LRCLDM.
2. Lost River at Walter Flat, WFLAT.
3. Mowitz Creek just downstream of the 136 bridge, MOWCRK.
4. Boles Creek just upstream of the 136 ford, BCFORD.
5. No. Fork Willow Creek below the Great Society Bridge, WCGSB.
6. Fletcher Creek just upstream of the 73 ford, FCFORD.

Two stations are on the Upper Lost River mainstem; one is downstream of the dam and the other at Walter Flat. Station LRCLDM is at a point about 1,000 meters downstream of Clear Lake Reservoir dam. Station WFLAT is at a point about 10 meters downstream of the Walter Flat Bridge, about eight miles downstream of the dam. In addition to the two stations on the Upper Lost River, there were four monitoring locations in streams that lead to Clear Lake Reservoir, the source of the Lost River. One station was on North Fork Willow Creek, the main tributary to Clear Lake Reservoir and the primary spawning stream for the endangered Lost River and Shortnose suckers. Two other sites, on Boles and Fletcher Creeks, drain into Willow Creek. The fourth site, on Mowitz Creek, drains directly into Clear Lake Reservoir but does not contribute much water to the reservoir. This site was added late in the investigation because of the opportunity to add to a sparse dataset. All of the sites, except the station below the dam, were accessible only during late spring to early fall because wet weather made the roads impassable. Sampling locations were limited to areas that could be reached by truck. Logistical issues precluded sampling in Clear Lake Reservoir.

Temporal Representation:

Sampling represents only one full season, late spring to early fall. Sampling included monthly grab samples and instantaneous measurements for one season, continuous temperature monitoring for one season, and two short continuous multiparameter deployments. The sampling periods do not correspond to the time periods that the suckers are in the streams. There were limited spots at which the streams could be accessed; these might not correspond to the points that provide representative data. Drawing conclusions about the impact of water temperature and nutrients on suckers based on sampling during summer, however, is justified because those months represent the conditions worse than the fish encounter during their time in the streams. Water temperature in the Upper Lost River/Clear Lake Reservoir watershed was investigated using: Remote continuous water and air temperature monitors (Optic stowaway data loggers) that took readings every 15 minutes from May through September 2002. Remote sensors that measured air temperature (Optic stowaway data loggers) and relative humidity (HOBO instruments) every 15 minutes for three days in June 2003. Solar pathfinder measurements to calculate solar radiation that reached stream surfaces. A thermal infrared aerial survey in July 2001and computer simulation modeling using the SSTEMP model. The monitoring instrument at the Boles Creek station was out of the water during that period due to seasonal dewatering and the sampling at Mowitz Creek did not begin until the following month.

Environmental Conditions:

There are no point source waste discharges within the watershed. The land use operations that may impact the Upper Lost River watershed as nonpoint sources of water pollution are livestock operations (grazing) and timber harvest.

QAPP Information:

NCRWQCB QA Procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157139, Temperature, water	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1661

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Preservation of Rare & Endangered Species

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Species listed under the federal Endangered Species Act are found in the study area, Lost River Suckers and Shortnose Suckers are classified as endangered species. The most sensitive beneficial uses most likely relate to the protection of the endangered sucker species. These fish can tolerate poor water quality such as low dissolved oxygen, high water temperature, and elevated pH levels, but the fish may not thrive at long-term, continual poor conditions resulting from habitat fragmentation, hydrologic regime alterations, and water diversion. Clear Lake Reservoir appears to possess a healthy population of Lost River and Shortnose suckers compared to other populations in the Klamath and Lost River Basin. The water quality and habitat conditions in the reservoir and its tributaries are better than elsewhere in the Klamath River and Lost River basins. Although the North Coast Regional Water Quality Control Board Water Quality Control Plan (Basin Plan) lists a cold-water fishery beneficial use for the study area, the current or historical presence of cold-water fish could not be confirmed. Computer simulation modeling suggests that decreasing solar radiation by increasing shade over the streams that drain into Clear Lake Reservoir could decrease water temperatures. The potential for increasing the shade due to riparian vegetation, however, is unlikely in all of these streams except for Willow Creek because of the inability of the soils to support increased vegetative growth. The Upper Lost River is more sensitive to the water temperature of the water released from Clear Lake Reservoir than to solar radiation. Even at current shade levels, the water temperature in the watershed supports the most sensitive beneficial use, the endangered sucker species. The relative health of the Clear Lake Reservoir Shortnose and Lost River sucker population is notable. Given the significance of the Clear Lake Reservoir watershed to preserving the Lost River and Shortnose sucker populations, it is necessary to preserve the aquatic habitat from any harmful effects related to land use activities. Willow Creek and its tributaries (primarily Boles Creek) are the only spawning sites for the sucker populations; it is especially important to protect valuable properly functioning riparian conditions in this stream. Regional Water Board staff has seen no information showing that the natural range of water temperature or nutrient concentrations in the streams draining into Clear Lake Reservoir are outside of the natural range for that environment due to anthropogenic causes (North Coast RWQCB, 2004d).The Upper Lost River/Clear Lake Reservoir area is listed for nutrients and temperature in accordance with Section 303(d) of the federal Clean Water Act (CWA). The listing of the Upper Lost River/Clear Lake Reservoir watershed as impaired because of bio-stimulatory substances (nutrients) and high water temperature was made in 1996. In accordance with a consent decree, January 2005 is the deadline for adoption or de-listing of the TMDLs for the Upper Lost River/Clear Lake Reservoir area by the State of California. Investigation into the basis of the listings revealed that the listings were apparently conferred from the Klamath River listings and not based on data or information specific to the Upper Lost River and Clear Lake Reservoir watershed. The appropriateness of the nutrients and temperature listings in the Upper Lost River is explored in the TMDL analysis. If the listings had been confirmed a TMDL would have been developed, however, the listings were not confirmed and de-listing for the watershed (including Clear Lake Reservoir, the streams draining to Clear Lake Reservoir and the Upper Lost River between the Clear Lake Reservoir dam and the Oregon border) is recommended by NCRWQCB staff.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses. At no time or place shall the temperature of any COLD water be increased by more than 5°F above natural receiving water temperature. At no time or place shall the temperature of WARM intrastate waters be increased more than 5°F above natural receiving water temperature.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The data collection effort associated with this analysis consisted of three components: collection and review of existing data, water quality grab samples (and associated instantaneous field measurements), and the short-term use of continuous monitoring devices. Neither visual observations nor water quality sampling indicated impairment due to excess nutrients, although the turbidity levels in the reservoir and in the Upper Lost River probably suppress primary production. The high level of turbidity noted in the Upper Lost River is of concern, but was not the subject of this analysis.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

There are six monitoring locations total. Two stations are on the Upper Lost River mainstem, one is downstream of the dam and the other at Walter Flat. Station LRCLDM is at a point about 1,000 meters downstream of Clear Lake Reservoir dam. Station WFLAT is at a point about 10 meters downstream of the Walter Flat Bridge, about eight miles downstream of the dam. In addition to the two stations on the Upper Lost River, there were four monitoring locations in streams that lead to Clear Lake Reservoir, the source of the Lost River. One station was on North Fork Willow Creek, the main tributary to Clear Lake Reservoir and the primary spawning stream for the endangered Lost River and Shortnose suckers. Two other sites, on Boles and Fletcher Creeks, drain into Willow Creek. The fourth site, on Mowitz Creek, drains directly into Clear Lake Reservoir but does not contribute much water to the reservoir. This site was added late in the investigation because of the opportunity to add to a sparse dataset. Logistical issues precluded sampling in Clear Lake Reservoir.

Temporal Representation:

Water temperature in the Upper Lost River/Clear Lake Reservoir watershed was investigated using: Remote continuous water and air temperature monitors (Optic stowaway data loggers) that took readings every 15 minutes from May through September 2002. Remote sensors that measured air temperature (Optic stowaway dataloggers) and relative humidity (HOBO instruments) every 15 minutes for three days in June 2003. Solar pathfinder measurements to calculate solar radiation that reached stream surfaces. A thermal infrared aerial survey in July 2001and computer simulation modeling using the SSTEMP model. All of the sites, except the station below the dam, were accessible only during late spring to early fall because wet weather made the roads impassable. Sampling locations were limited to areas that could be reached by truck.

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed for the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157139, Temperature, water	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

329260

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:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Temperature.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

According to Carter (2008) the lethal temperature evaluation guideline for salmonid spawning, egg incubation & fry emergence is 20C.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	102599	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3 of the Listing Policy. Under section 3 a single line of evidence are necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 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 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 102599, Aldrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44965

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Aldrin. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Survey. A Report of the Surface Water Ambient Monitoring Program (SWAMP). California State Water Resources Control Board, Sacramento, CA

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life. (Water Quality Control Plan, North Coast Basin)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Aldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Data for this line of evidence for Reservoir F (Modoc County) was collected at 1 monitoring site [ Reservoir F - 105TF0007]. Samples were collected from 1 location. Individual sample locations consisted of an area within a given waterbody from which fish tissue samples were collected. The number of sample locations per waterbody was based on the overall size of the waterbody (SWAMP, 2010). Specifics of individual sampling locations can be found in the supplemental report entitled "Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008" (SWAMP, 2008).

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Samples were collected, processed, and analyzed in accordance with the methods described in Quality Assurance Project Plan "Screening Study of Bioaccumulation in California Lakes and Reservoirs." (SWAMP, 2008).

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 102599, Aldrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44966

Pollutant:

Aldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	157141	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Alkalinity as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 157141, Alkalinity as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113180

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 USFS Management Indicator Species - Streams data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs 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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FLH087)

Temporal Representation:

The samples were collected between the dates of 2012-06-12 and 2012-06-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157141, Alkalinity as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

111690

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 Perennial Stream Surveys data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs 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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157141, Alkalinity as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

323117

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm 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 Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. (Basin Plan, 2018)

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157141, Alkalinity as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

323118

Pollutant:

Alkalinity as CaCO3

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157141, Alkalinity as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113186

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:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157141, Alkalinity as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113166

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:

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	161410	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Ammonia
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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113169

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

114069

Pollutant:

Nitrogen, ammonia (Total Ammonia)

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:

Water Board staff assessed DFW_ABL_Monitoring data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs 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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

105107

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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

323415

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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 Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

323522

Pollutant:

Nitrogen, ammonia (Total Ammonia)

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

323525

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

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 Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

105196

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113185

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113168

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113174

Pollutant:

Nitrogen, ammonia (Total Ammonia)

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

117047

Pollutant:

Nitrogen, ammonia (Total Ammonia)

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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113190

Pollutant:

Nitrogen, ammonia (Total Ammonia)

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The USEPA Health Advisory for lifetime exposure to Ammonia as a drinking water level is a concentration of 30 mg/L

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 161410, Ammonia	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113172

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	169288	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. One line of evidence evaluating benthic-macroinvertebrate bioassessment data is available in the administrative record to assess this indicator. One of one benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. However, a minimum of two benthic-macroinvertebrate samples are needed to assess listing status. 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 does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. One of one benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. The available information is insufficient to determine whether the waterbody/pollutant combination should be placed on the 303(d) List of impaired waters at this time. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 169288, Benthic Community Effects	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

352525

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:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 105FLH087 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the water quality standard. CSCI scores were from 0.464770444 to 0.464770444 .

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board (NCRWQCB 2018).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rhen, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.)

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

Samples were collected from 2016-07-19 to 2016-07-19.

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	166132	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166132, Chlordane	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44975

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlordane, Total. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). Total chlordane was calculated as the sum of the following chlordane isomers: cis- and trans-chlordane, cis- and trans-nonachlor, and oxychlordane.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2011): No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. There shall be no bioaccumulation of pesticide concentrations found in bottom sediments or aquatic life.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for total chlordane in fish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166132, Chlordane	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44976

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total Chlordane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166132, Chlordane	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44984

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	157134	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Chloride
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

328105

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:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The secondary maximum contaminant level listed in Table 64449-B for chloride is 250 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

324043

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

324033

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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 Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The chloride criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 230000 ug/L (230 mg/L)(USEPA National Recommended Water Quality Criteria, 2006).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113175

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

110267

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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

328100

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm 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 EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

111767

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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157134, Chloride	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113188

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	103749	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. None samples exceed the objectives. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the 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 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 103749, Dieldrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44876

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Dieldrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 103749, Dieldrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

45001

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Dieldrin. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for dieldrin in fish tissue is 0.32 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 103749, Dieldrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

45002

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	166133	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166133, Endrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44949

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Endrin concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166133, Endrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44948

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for endrin in fish tissue is 660 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166133, Endrin	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44950

Pollutant:

Endrin

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	155242	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Hardness as CaCO3
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 155242, Hardness as CaCO3	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

318056

Pollutant:

Hardness as CaCO3

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:

Water Board staff assessed the hardness data and determined that 1 of 1 sample for 2016 exceeds the water quality objective.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The hardness shall conform to the values listed in Table 3-1 which states that the 50% upper limit hardness 50 mg/L. The 50% upper limit represents the 50 percentile values for a calendar year so that 50% or more of the values must be less than or equal to the upper limit.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

This sample was collected at sampling station name: Fletcher Creek (USFS); station code: 105FLH087.

Temporal Representation:

This sample was collected on 7/19/2016.

Environmental Conditions:

QAPP Information:

QAPP for SWAMP Reference Condition Management Plan

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	166134	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166134, Heptachlor	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44969

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Heptachlor. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166134, Heptachlor	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44968

Pollutant:

Heptachlor

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	166135	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166135, Heptachlor epoxide	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44978

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Heptachlor epoxide. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Heptachlor Epoxide concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166135, Heptachlor epoxide	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44977

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Heptachlor epoxide. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in fish tissue is 0.93 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166135, Heptachlor epoxide	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44986

Pollutant:

Heptachlor epoxide

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Heptachlor epoxide. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	166136	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166136, Hexachlorobenzene/ HCB	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44987

Pollutant:

Hexachlorobenzene/ HCB

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Hexachlorobenzene. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in fish tissue is 2.8 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	166137	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166137, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44958

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum Lindane concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166137, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44957

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for lindane in fish tissue is 4.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166137, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44967

Pollutant:

Lindane/gamma Hexachlorocyclohexane (gamma-HCH)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	170529	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Mercury
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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.5 of the Listing Policy. Under section 3.5 a single line of evidence is necessary to assess listing status. Five lines of evidence are available in the administrative record to assess the pollutant. COMM (Sport fish objective) Fish used in the COMM assessment are limited to lengths that are within Calif. Dept. of Fish and Wildlife legal size limits applicable to this waterbody. LOE 133956: 0 of 1 samples exceed the mercury objective and consist of 12 trophic level 4 fish. (CDFW legal limit) LOE 322658: 0 of 1 samples exceed the mercury objective and consist of 14 trophic level 4 fish. (CDFW legal limit) WILD (Prey fish objective) LOE 322672: 0 of 1 samples exceed the mercury objective and consist of 20 50-150mm prey fish. WILD (Sport fish objective) LOE 133957: 0 of 1 samples exceed the mercury objective and consist of 12 trophic level 4 fish. (CDFW legal limit) LOE 322645: 0 of 1 samples exceed the mercury objective and consist of 14 trophic level 4 fish. (CDFW legal limit) 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. Tissue samples were compared with the sport fish objective and 2 of 2 samples exceed for WILD beneficial use and 2 of 2 samples exceed for the COMM beneficial use. The samples consist of trophic level 4 fish and are from a minimum of 2 annual averages and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Tissue samples were compared with the prey fish objective and 0 of 1 samples exceed WILD beneficial use. The sample consists of 20 fish and may contain a mix of trophic levels. One exceeding sample of eight or more fish is needed to determine non-attainment of the mercury objective following weight of evidence in Listing Policy section 3.11. 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 Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	Decision written by SWRCB staff.

Line of Evidence (LOE) for Decision ID 170529, Mercury	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

322658

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Contamination in Lakes and Resrv data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and the results are as follows: 0 of 1 sample exceeded the water quality threshold for Mercury. Monitors collected 14 composites of Largemouth Bass composed of 1 fish each. This LOE contains data only for trophic level 4 fish whose average length was inside the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations. Fish collected within the same calendar year were averaged into a single sample for comparison with the objective. All 14 fish were collected in a single calendar year, which resulted in 1 independent sample.

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of the Commercial and Sport Fishing beneficial comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline 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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 105TF0007 (Reservoir F).

Temporal Representation:

Data for this line of evidence were collected between 2019-08-13 and 2019-08-13. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 170529, Mercury	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

133956

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Mercury. This LOE contains data only for trophic level 4 fish. Twelve composites (1 fish per composite) were generated from one species (largemouth bass) and were averaged for comparison with the objective. This LOE does not contain data from fish with an average length outside of the legal size limits as described by the California Department of Fish and Wildlife Fishing Regulations.

Data Reference:

Statewide Lakes Sportfish Contamination Study 2007 2008

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline 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

Spatial Representation:

Data for this line of evidence for Reservoir F (Modoc County) was collected at 1 monitoring site [ Reservoir F - 105TF0007].

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 170529, Mercury	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

133957

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Statewide Lakes Sportfish Contamination Study 2007 2008

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The Statewide Sport Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.2 mg/Kg wet weight skinless fillet samples of trophic level 3, or trophic level 4 fish (whichever is highest in the water body) over a one year averaging period. If trophic level 3 fish are used in the assessment then the Prey Fish Water Quality Objective must also be used to determine that the Sport Fish Objective is being met. Trophic levels of applicable fish are defined in, but not limited to those in Attachment C of the Final Regulatory Language document (Appendix A) of State Water Resources Control Board Resolution No. 2017-0027.

Guideline 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

Spatial Representation:

Data for this line of evidence for Reservoir F (Modoc County) was collected at 1 monitoring site [ Reservoir F - 105TF0007].

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 170529, Mercury	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

322645

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline 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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 105TF0007 (Reservoir F).

Temporal Representation:

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 170529, Mercury	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

322672

Pollutant:

Mercury

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Wildlife 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 Sportfish Contamination in Lakes and Resrv data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and the results are as follows: 0 of 1 sample exceeded the water quality threshold for Mercury. Monitors collected 2 composites: 1 composite of Bluegill composed of 10 fish and 1 composite of Largemouth Bass composed of 10 fish. All fish collected within the same calendar year with a reported length of 50-150 mm were averaged into a single sample, independent of species or trophic level, for comparison with the objective. All 20 fish were collected in a single calendar year, which resulted in 1 independent sample.

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The Statewide Prey Fish Water Quality Objective for the protection of Wildlife Habitat comes from the Statewide Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, and is 0.05 mg/Kg wet weight whole fish samples of any fish species between 50 to 150 mm in total length collected between February 1 and July 31. (SWRCB Resolution No. 2017-0027)

Guideline 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

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 105TF0007 (Reservoir F).

Temporal Representation:

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	166138	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166138, Mirex	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44996

Pollutant:

Mirex

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 0 samples exceed the criterion for Mirex. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). One sample was not used in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for mirex in fish tissue is 0.28 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	157135	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 157135, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

119337

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 SWAMP Perennial Stream Surveys .

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, North Coast Basin is 10.0 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157135, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113167

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157135, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113171

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157135, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

102725

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157135, Nitrate/Nitrite (Nitrite + Nitrate as N)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

325775

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nitrate + Nitrite as N.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	104982	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of 1 samples from the North Fork Willow Creek exceed the objective for the protection of MUN. 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 1 samples from the North Fork Willow Creek exceed the objective for the protection of MUN 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 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 104982, Nitrogen, Nitrate	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

104207

Pollutant:

Nitrogen, Nitrate

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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Water Quality Control Plan, North Coast Basin is 10.0 mg/L (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	104983	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board 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 1 samples from the North Fork Willow Creek exceed the objective for the protection of MUN. 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 1 samples from the North Fork Willow Creek exceed the objective for the protection of MUN 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 3.1. 4. Pursuant to Section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 104983, Nitrogen, Nitrite	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

102714

Pollutant:

Nitrogen, Nitrite

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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2018): Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15. The maximum contaminant level listed in Table 64431-A for Nitrite as N is 1.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157136	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Oxygen, Dissolved
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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

326277

Pollutant:

Oxygen, Dissolved

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for COLD beneficial use waters to be a daily minimum of 6.0 mg/L and a 7-day moving average of 8.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

328881

Pollutant:

Oxygen, Dissolved

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:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

328812

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for SPAWN beneficial use waters to be a daily minimum of 9.0 mg/L and a 7-day moving average of 11.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

328795

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm 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 EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

326286

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm 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 Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

326244

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for SPAWN beneficial use waters to be a daily minimum of 9.0 mg/L and a 7-day moving average of 11.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113170

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113184

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

107235

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113177

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm 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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FLH087)

Temporal Representation:

The samples were collected between the dates of 2012-06-12 and 2012-06-12

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

133903

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Species listed under the federal Endangered Species Act are found in the Upper Lost River and Clear Lake, Boles HSA include the Lost River Suckers and Shortnose Suckers. The most sensitive beneficial uses relate to the protection of the endangered sucker species, which are warm water species (WARM). These fish can tolerate poor water quality such as low dissolved oxygen, high water temperature, and elevated pH levels, but the fish may not thrive at long-term, continual poor conditions resulting from habitat fragmentation, hydrologic regime alterations, and water diversion. Clear Lake Reservoir appears to possess a healthy population of Lost River and Shortnose suckers compared to other populations in the Klamath and Lost River Basin. The water quality and habitat conditions in the reservoir and its tributaries are better than elsewhere in the Klamath River and Lost River basins. Although the North Coast Regional Water Quality Control Board Water Quality Control Plan (Basin Plan) also lists a cold-water fishery beneficial use for the study area, the current or historical presence of cold-water fish could not be confirmed. Computer simulation modeling suggests that decreasing solar radiation by increasing shade over the streams that drain into Clear Lake Reservoir could decrease water temperatures. The potential for increasing the shade due to riparian vegetation, however, is unlikely in all of these streams except for Willow Creek because of the inability of the soils to support increased vegetative growth. The Upper Lost River is more sensitive to the water temperature of the water released from Clear Lake Reservoir than to solar radiation. Even at current shade levels, the water temperature in the watershed supports the most sensitive beneficial use, the endangered sucker species. The relative health of the Clear Lake Reservoir Shortnose and Lost River sucker population is notable. Given the significance of the Clear Lake Reservoir watershed to preserving the Lost River and Shortnose sucker populations, it is necessary to preserve the aquatic habitat from any harmful effects related to land use activities. Willow Creek and its tributaries (primarily Boles Creek) are the only spawning sites for the sucker populations; it is especially important to protect valuable properly functioning riparian conditions in this stream.

Data Reference:

Total daily maximum load analysis-water temperature and nutrients. Upper Lost River and Clear Lake Reservoir Watershed. Santa Rosa, CA: North Coast RWQCB

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states: Dissolved oxygen concentrations shall conform to those limits listed in Section 3.3.5. Section 3.3.5 lists dissolved oxygen concentration limits for the WARM beneficial use waters to be a daily minimum of 5.0 mg/L and a 7-day moving average of 6.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Total daily maximum load analysis-water temperature and nutrients. Upper Lost River and Clear Lake Reservoir Watershed. Santa Rosa, CA: North Coast RWQCB

Spatial Representation:

Information applies to the Klamath River HU, Lost River HA, Clear Lake, Boles HSAs waterbody.

Temporal Representation:

Information applies year-round.

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed for the TMDL analysis.

QAPP Information Reference(s):

Placeholder reference 2006 303(d)

QAPP Information Reference(s):

Total daily maximum load analysis-water temperature and nutrients. Upper Lost River and Clear Lake Reservoir Watershed. Santa Rosa, CA: North Coast RWQCB

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1665

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Dissolved oxygen levels are above the existing numeric water quality objectives. There is no evidence of impacts from nutrients, dissolved oxygen, or other nutrient related effects on the sensitive species of concern. The beneficial uses appear to be unaffected by water temperature. The natural range of water temperatures and nutrient concentrations above Clear Lake Reservoir do not appear to be affected by anthropogenic activities. There is no evidence that the biostimulatory narrative objective is exceeded. The system appears to be nitrogen limited and nitrogen levels are far below levels expected to cause biostimulation in this system. Although, phosphorus levels are elevated in comparison to U.S. EPA suggested levels, these suggested levels are not relevant because there is no evidence of excessive algal growth in the reservoir and the system appears to be nitrogen limited.The Upper Lost River/Clear Lake Reservoir area is listed as impaired for nutrients and temperature in accordance with Section 303(d) of the federal Clean Water Act (CWA). The listing of the Upper Lost River/Clear Lake Reservoir watershed as impaired because of biostimulatory substances (nutrients) and high water temperature was made in 1996. In accordance with a consent decree, January 2005 is the deadline for adoption or de-listing of the TMDLs for the Upper Lost River/Clear Lake Reservoir area by the State of California. Investigation into the basis of the listings revealed that the listings were apparently conferred from the Klamath River listings and not based on data or information specific to the Upper Lost River and Clear Lake Reservoir watershed. The appropriateness of the nutrients and temperature listings in the Upper Lost River is explored in the TMDL analysis. If the listings had been confirmed a TMDL would have been developed, however, the listings were not confirmed and de-listing for the watershed (including Clear Lake Reservoir, the streams draining to Clear Lake Reservoir and the Upper Lost River between the Clear Lake Reservoir dam and the Oregon border) is recommended by NCWRQCB staff.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Table 3.1, Specific Water Quality Objectives for North Coast Region Clear Lake, Upper & Lower Lost River, Tule Lake, Lower Klamath Lake: > 5.0 mg/l, minimum 8.0 mg/l, 50% lower limit (this means that 50% or more of the
monthly mean values must be equal to or greater than 8.0 mg/l). Other Streams in Upper Lost River HA: > 7.0 mg/l, minimum 8.0 mg/l, 50% lower limit (this means that 50% or more of the monthly mean values must be equal to or greater than 8.0 mg/l).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Continuous dissolved oxygen measurements made in the Upper Lost River at Walter Flat from September 30 to October 2, 2002.

Temporal Representation:

Continuous dissolved oxygen measurements using a YSI Datasonde 6600 that measured dissolved oxygen in 15-minute increments were made in the Upper Lost River at Walter Flat from September 30 to October 2, 2002.

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 157136, Oxygen, Dissolved	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1666

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The TMDL Analysis was completed for Upper Lost River and Clear Lake Reservoir Watershed. The Upper Lost River/Clear Lake Reservoir area is not listed for dissolved oxygen. This parameter, however, can be impacted by excessive biomass growth related to high nutrient concentrations. Diurnal cycles of algal respiration can lead to water that is photosynthetically supersaturated with dissolved oxygen in late afternoons and depressed in very early mornings by overnight respiration.

The most sensitive beneficial use that could be impacted by low dissolved oxygen concentrations is the ESA-listed sucker species. The amount of dissolved oxygen in water at 100% saturation is partly dependent on the altitude; the sampling stations in this analysis ranged in altitude from 4,163 to 4,921 feet above sea level. The water at this altitude can hold less dissolved oxygen, at 100% saturation, than water at lower elevations. Dissolved oxygen data at the six sampling stations consisted of instantaneous measurements at the time that grab samples were obtained and of two brief periods of continuous measurement. The Basin Plan objectives for dissolved oxygen in the Upper Lost River/Clear Lake Reservoir area are 5.0 mg/l as a minimum and 8.0 as a 50% lower limit.

There were 57 instantaneous measurements of dissolved oxygen ranging from 6.1 mg/l to 13.02 mg/l. The mean value of these measurements is 8.83 mg/l, with a median of 8.53 mg/l, and a lower 95% confidence level of 8.44 mg/l. The high value of 13.02 mg/l was obtained at the Boles Creek station in October 2002 at a time when there was no surface flow; this value was taken at 14:30 and may represent a photosynthetically supersaturated condition. Field notes state that heavy algal growth was noted in the pool upstream of the dewatered area where samples were taken. The lowest values were still above the minimum required by the Basin Plan. The lowest value, 6.1 mg/l was obtained at 17:30 in June 2003 at Walter Flat. The next lowest value, 6.55 mg/l was obtained at 08:30 in August 2001 at the station just downstream of Clear Lake Reservoir dam.

Continuous dissolved oxygen measurements using a YSI Datasonde 6600 that measured dissolved oxygen, pH, specific conductivity, and water temperature at 15-minute increments were made in the Upper Lost River at Walter Flat from September 30 to October 2, 2002. The data show a diurnal variation with a low of 9.59 mg/l and a high of 12.11 mg/l. The mean is 10.47 mg/l, the median is 10.34 mg/l, and the 95% lower confidence level is 10.38 mg/l. A Datasonde also was deployed at this station from June 9 through June 11, 2003. Again, a diurnal cycle is seen. The data from this sampling episode show warmer temperatures and lower dissolved oxygen concentrations, ranging from a low of 5.42 mg/l to a high of 6.32 mg/l. The mean of the measurements is 5.87 mg/l, the median is 5.85 mg/l, and the lower 95% confidence interval is 5.82 mg/l.

Similarly, continuous dissolved oxygen measurements using a YSI Datasonde 6600 that measured dissolved oxygen, pH, specific conductivity, and water temperature at 15-minute increments were made in the Willow Creek sampling station from September 30 to October 2, 2002. The data show variation with a low of 10.03 mg/l and a high of 13.74 mg/l. The mean is 12.03 mg/l, the median is 12.11 mg/l, and the 95% lower confidence level is 11.89 mg/l. A Datasonde also was deployed at this station from June 10 through June 12, 2003. Again, a diurnal cycle is seen. The data from this sampling episode show warmer temperatures and lower dissolved oxygen concentrations, ranging from a low of 3.61 mg/l to a high of 12.1 mg/l. The mean of the measurements is 7.09 mg/l, the median is 6.69 mg/l, and the lower 95% confidence interval is 6.69 mg/l (North Coast RWQCB, 2004d).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Dissolved Oxygen, Table3.1 Specific Water Quality Objectives for North Coast Region Clear Lake, Upper & Lower Lost River, Tule Lake, Lower Klamath Lake:
> 5.0 mg/l, minimum 8.0 mg/l, 50% lower limit (this means that 50% or more of the monthly mean values must be equal to or greater than 8.0 mg/l).
Other Streams in Upper Lost River HA:
> 7.0 mg/l, minimum 8.0 mg/l, 50% lower limit (this means that 50% or more of the monthly mean values must be equal to or greater than 8.0 mg/l).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Specific WQOs in the Basin Plan Table 3.1.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

The monitoring locations for the Upper Lost River/Clear Lake Reservoir area are:
1. Lost River below Clear Lake Reservoir dam, LRCLDM.
2. Lost River at Walter Flat, WFLAT.
3. Mowitz Creek just downstream of the 136 bridge, MOWCRK.
4. Boles Creek just upstream of the 136 ford, BCFORD.
5. No. Fork Willow Creek below the Great Society Bridge, WCGSB.
6. Fletcher Creek just upstream of the 73 ford, FCFORD.

Two stations are on the Upper Lost River mainstem, one is downstream of the dam and the other at Walter Flat. Station LRCLDM is at a point about 1,000 meters downstream of Clear Lake Reservoir dam. Station WFLAT is at a point about 10 meters downstream of the Walter Flat Bridge, about eight miles downstream of the dam. In addition to the two stations on the Upper Lost River, there were four monitoring locations in streams that lead to Clear Lake Reservoir, the source of the Lost River. One station was on North Fork Willow Creek, the main tributary to Clear Lake Reservoir and the primary spawning stream for the endangered Lost River and shortnose suckers. Two other sites, on Boles and Fletcher Creeks, drain into Willow Creek. The fourth site, on Mowitz Creek, drains directly into Clear Lake Reservoir but does not contribute much water to the reservoir. This site was added late in the investigation because of the opportunity to add to a sparse dataset. All of the sites, except the station below the dam, were accessible only during late spring to early fall because wet weather made the roads impassable. Sampling locations were limited to areas that could be reached by truck. Logistical issues precluded sampling in Clear Lake Reservoir.

Temporal Representation:

Data from August 2001 through June 2003 at different stations. Continuous dissolved oxygen measurements using a YSI Datasonde 6600 that measured dissolved oxygen, pH, specific conductivity, and water temperature at 15-minute increments were made in the Upper Lost River at Walter Flat, Willow Creek Sampling Station, from September 30 to October 2, 2002. A Datasonde also was deployed at Upper Lost River at Walter Flat station from June 9 through June 11, 2003. Measurements taken at Boles Creek station in October 2002 at a time when there was no surface flow. Measurements taken at August 2001 at the station just downstream of Clear Lake Reservoir dam.

Environmental Conditions:

QAPP Information:

NCRQWQCB QA procedures followed for the TMDL analysis.

QAPP Information Reference(s):


DECISION ID	166139	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166139, PCBs (Polychlorinated biphenyls)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

45003

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for PCB, Total. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). Total PCB was assessed for as follows: PCB aroclors and congeners were summed separately and the sum that yielded the highest value was used for the assessment.

Data Reference:

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2011): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for polychlorinated biphenyls in fish tissue is 2.6 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166139, PCBs (Polychlorinated biphenyls)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

45004

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total PCB concentration of 500 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166139, PCBs (Polychlorinated biphenyls)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44878

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	157137	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Selenium
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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 157137, Selenium	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

322746

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP Sportfish Contamination in Lakes and Resrv data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and the results are as follows: 0 of 3 samples exceeded the water quality threshold for Selenium. Monitors collected 3 composites: 1 composite of Bluegill composed of 10 fish, 1 composite of Largemouth Bass composed of 9 fish, and 1 composite of Largemouth Bass composed of 10 fish. Because no composites were collected within the same averaging period, these composites represent 3 independent samples.

Data Reference:

Habitat, Tissue, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The OEHHA Fish Contaminant Goal for selenium in fish tissue is 7.4 ppm. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A background dietary consumption rate of 0.114 mg/day is applied for this micronutrient. (Klasing, S., and R. Brodberg, 2008)

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Data were collected from 1 station(s). Station Code(s): 105TF0007 (Reservoir F).

Temporal Representation:

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157137, Selenium	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44879

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Selenium. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	158417	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Sodium
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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 158417, Sodium	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

329055

Pollutant:

Sodium

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:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 158417, Sodium	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

102432

Pollutant:

Sodium

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:

Water Board staff assessed DFW_ABL_Monitoring data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality standard for Sodium.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Per the Drinking Water Standards and Health Advisories (USEPA 2012), the health advisory for sodium for individuals on a sodium-restricted diet is 20 mg/l.

Guideline Reference:

2012 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 158417, Sodium	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

114070

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural 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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Water Quality for Agriculture, published by the Food and Agriculture Organization of the United Nations in 1985, contains criteria protective of various agricultural uses of water, including irrigation of various types of crops and stock watering. At or below the sodium threshold of 69 mg/L, agricultural uses of water should not be limited.

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 158417, Sodium	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

329130

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Sodium.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Water Quality for Agriculture, Food and Agriculture Organization of the United Nations - Irrigation and Drainage Paper No. 29, Rev 1, Rome (1985)

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	163022	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 163022, Specific Conductivity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

318933

Pollutant:

Specific Conductivity

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 specific conductivity data for EPA National Aquatic Resources Survey (NARS) and determined that calendar year 2014 exceeds the 50% upper limit, so that 1 of 1 sample exceeds the water quality objective.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Per the Basin Plan (NCRWQCB 2007): The 90% upper limit specific conductance objective at 77 F is 250 micromhos (or mS/cm2). The 50% upper limit specific conductance objective at 77 F is 150 micromhos (or mS/cm2). The 90% and 50% upper limits represent the 90/50 percentile values for a calendar year. 90% or 50% or more of the values must be less than or equal to the upper limit.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

This sample was collected at sampling station name: North Fork Willow Creek; station code: NARS_WQX-CALS-1116.

Temporal Representation:

This sample was collected on 8/5/2014.

Environmental Conditions:

QAPP Information:

QAPP for EPA National Aquatic Resources Survey (NARS)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 163022, Specific Conductivity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

318058

Pollutant:

Specific Conductivity

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 specific conductivity data for parent project SWAMP Reference Condition Management Plan and determined calendar year 2016 exceeds the 50% upper limit, so that 1 of 1 sample exceeds the water quality objective.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

This sample was collected at sampling station name: Fletcher Creek (USFS); station code: 105FLH087.

Temporal Representation:

This sample was collected on 7/19/2016.

Environmental Conditions:

QAPP Information:

QAPP for SWAMP Reference Condition Management Plan

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 163022, Specific Conductivity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100740

Pollutant:

Specific Conductivity

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:

Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality standard for specific conductance. Data range from 241 micromhos.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: Specific conductivity shall conform to Table 3-1 which states that water quality objective for specific conductivity has an 90% upper limit of 250 micromhos and a 50% upper limit of 150 micromhos.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates 06/26/2013.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 163022, Specific Conductivity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100746

Pollutant:

Specific Conductivity

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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) Boles Creek ~2.5mi below Hwy 136 (105PS1492)

Temporal Representation:

The samples were collected between the dates 08/06/2014.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 163022, Specific Conductivity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100761

Pollutant:

Specific Conductivity

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s)Fletcher Creek (USFS)
Rd. (105FLH087).

Temporal Representation:

The samples were collected between the dates 06/12/2012.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	157138	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Sulfates
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 157138, Sulfates	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113173

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157138, Sulfates	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

329198

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:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Sulfate.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157138, Sulfates	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

326852

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:

Water Board staff assessed SWAMP Reference Condition Management Plan data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Sulfate.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157138, Sulfates	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

102913

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 SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105PS1492)

Temporal Representation:

The samples were collected between the dates of 2014-08-06 and 2014-08-06

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157138, Sulfates	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113179

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105NWC151)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 and 2013-06-26

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 157138, Sulfates	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

113899

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 DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) (105FC1116)

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	166140	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 166140, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44985

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009). Total DDT was calculated as the sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD.

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for total DDT in fish tissue is 15 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166140, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44994

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total DDT concentration of 1000 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 166140, Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44993

Pollutant:

Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	157140	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

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

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 157140, Turbidity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

329386

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed EPA National Aquatic Resources Survey (NARS) data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Chapter 15, Division 4, Article 4, Section 64435 (Tables 2 and 3), and Section 64444.5 (Table 5), and listed in Table 3-2 of this Plan (Water Quality Control Plan, North Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

California Maximum Contaminant Levels (MCLs) apply to ambient surface waters under the 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: NARS_WQX-CALS-1116 (North Fork Willow Creek).

Temporal Representation:

The samples were collected between the dates of 2014-08-05 and 2014-08-05

Environmental Conditions:

QAPP Information:

Generic SWAMP QAPrP

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 157140, Turbidity	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

327321

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:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

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: 105FLH087 (Fletcher Creek (USFS)).

Temporal Representation:

The samples were collected between the dates of 2016-07-19 and 2016-07-19

Environmental Conditions:

QAPP Information:

QAPP for Surface Water Ambient Monitoring Program (SWAMP)

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	104065	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	alpha-Endosulfan (Endosulfan 1)
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence are necessary to assess listing status. Three line(s) of evidence are available in the administrative record to assess this pollutant. None of the samples exceed the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None 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 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 104065, alpha-Endosulfan (Endosulfan 1)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44941

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP data for Reservoir F (Modoc County) to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endosulfan I. One composite (5 fish per composite) was generated from one species: largemouth bass. Details of the compositing protocol can be found in the March 2009 report entitled: "Contaminants in Fish from California Lakes and Reservoirs: Technical Report on Year One of a Two-Year Screening Study" (SWAMP, 2009).

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

National Academy of Science guidelines (NAS 1972) establish a maximum total Endosulfan concentration of 100 ug/Kg (wet weight) in tissue samples for protection of aquatic life from bioaccumulation of toxic substances.

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 104065, alpha-Endosulfan (Endosulfan 1)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44877

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in fish tissue is 13,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 32 g/day. A cooking reduction factor of 1 is applied for skin-off fillets.

Guideline Reference:

Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene

Guideline Reference:

Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments

Line of Evidence (LOE) for Decision ID 104065, alpha-Endosulfan (Endosulfan 1)	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

44940

Pollutant:

alpha-Endosulfan (Endosulfan 1)

LOE Subgroup:

Pollutant-Tissue

Matrix:

Tissue

Fraction:

Fish fillet

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fish tissue analysis

Data Used to Assess Water Quality:

Data Reference:

Cruise Report for the Surface Waters Ambient Monitoring Program (SWAMP) Bioaccumulation Screening Study in California Lakes and Reservoirs, Sampling Dates: June 2007- March 2008

Statewide Lakes Sportfish Contamination Study 2007 2008

Contaminants in Fish from California Lakes and Reservoirs, 2007-2008: Summary Report on a Two-Year Screening Survey

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

National Academy of Sciences. Water Quality Criteria 1972. EPA-R3-73-033. Washington, D.C.: U.S. Environmental Protection Agency

Spatial Representation:

Temporal Representation:

Data was collected on a single day 9/17/2007.

Environmental Conditions:

Staff is not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan Screening Study of Bioaccumulation in California Lakes and Reservoirs. Moss Landing Marine Labs. Prepared for SWAMP BOG, 49 pages plus appendices and attachments


DECISION ID	155241	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100725

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:

Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for pH. Data range from 8.9.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for DFW_ABL_Monitoring.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The pH shall conform to the values listed in Table 3-1 which states that the water quality objective for pH shall not be depressed below 7.0 or raised above 8.4.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) Willow Creek, NF ~8.3mi above Boles Cr.
(105FC1116)

Temporal Representation:

The samples were collected between the date 08/05/2014.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100721

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:

Water Board staff assessed the data for this water body to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality standard for pH. Data range from 7.8.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) Fletcher Creek (USFS)
Rd. (105FLH087)

Temporal Representation:

The samples were collected between the date 06/12/2012.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

QAPP not required for federal data.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100715

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 USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The pH shall conform to the values listed in Table 3-1 which states that the water quality objective for pH for water bodies in Clear Lake Reservoir & Upper Lost River shall not be depressed below 7.0 or raised above 8.5.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) Willow Creek, NF below Fourmile Cr.
(105NWC151)

Temporal Representation:

The samples were collected between the date 06/26/2013.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

318932

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:

Water Board staff assessed pH data for EPA National Aquatic Resources Survey (NARS) and determined 0 samples were less than pH 7.0 and 1 sample was greater than pH 8.4, so that 1 of 1 sample exceeds the water quality objective.

Data Reference:

WQX from the NWQMP for the 2026 Integrated Report in Region 1

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

This sample was collected at sampling station name: North Fork Willow Creek; station code: NARS_WQX-CALS-1116.

Temporal Representation:

This sample was collected on 8/5/2014.

Environmental Conditions:

QAPP Information:

QAPP for EPA National Aquatic Resources Survey (NARS)

QAPP Information Reference(s):

Generic SWAMP QAPrP

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100706

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:

Water Board staff assessed SWAMP Perennial Stream Surveys data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality standard for pH.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for SWAMP Perennial Stream Surveys .

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The pH shall conform to the values listed in Table 3-1 which states that the water quality objective for pH for water bodies in the Clear Lake Reservoir & Upper Lost River shall not be depressed below 7.0 or raised above 9.0.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) Boles Creek ~2.5mi below Hwy 136 (105PS1492)

Temporal Representation:

The samples were collected between the date 08/06/2014.

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

Quality Assurance Program Plan and Standard Operating Procedures for SWAMP program

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

100701

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:

Water Board staff assessed USFS Management Indicator Species - Streams data for Klamath River HU, Lost River HA, Clear Lake, Boles HSAs to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality standard for pH.

Data Reference:

Water Quality Assessment Data for the 2018 solicitation cycle submitted through CEDEN for USFS Management Indicator Species - Streams .

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Basin, Chapter III, General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The pH shall conform to the values listed in Table 3-1 which states that the water quality objective for pH for water bodies in the Clear Lake Reservoir & Upper Lost River shall not be depressed below 7.0 or raised above 9.0.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s) Willow Creek ~3mi below Boles Cr. (105WLC135)

Temporal Representation:

The samples were collected between the dates of 2013-06-26 to 2013-06-26

Environmental Conditions:

There are no known environmental conditions (e.g., seasonality, land use practices, fire events, storms, etc.) that are related to these data.

QAPP Information:

QAPP not required for federal data

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 155241, pH	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

318057

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:

Water Board staff assessed the data and determined that 0 samples were less than pH 6.5 and 0 samples were greater then pH 8.5, so that 0 of 1 sample exceeds the water quality objective for pH.

Data Reference:

Benthic, Field, Habitat, WQ from the Surface Water Ambient Monitoring Program for the 2026 Integrated Report in Region 1

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

This sample was collected at sampling station name: Fletcher Creek (USFS); station code: 105FLH087.

Temporal Representation:

This sample was collected on 7/19/2016.

Environmental Conditions:

QAPP Information:

QAPP for SWAMP Reference Condition Management Plan

QAPP Information Reference(s):

Generic SWAMP QAPrP


DECISION ID	68771	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

Pollutant:	Nutrients
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Water Board conclusion: This pollutant was considered for placement on the section 303(d) List in a previous Integrated Report cycle. No new information was reviewed for this current Integrated Report cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for removal from the Section 303(d) List under Section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Eight lines of evidence are available in the administrative record to assess this pollutant. There is no evidence that the biostimulatory narrative objective is exceeded. The North Coast RWQCB staff summary of the Upper Lost River De-Listing Recommendation along with the TMDL Analysis Staff Report support the decision to remove nutrients from the 303(d) List for this water segment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing this water segment-pollutant combination from the section 303(d) list in the Water Quality Limited Segments category (i.e., sufficient justification to de-list). This conclusion is based on the staff findings that: (1) The sediment quality guideline used complies, with the requirements of Section 6.1.3 of the Policy. (2) The data used satisfies the data quality requirements of Section 6.1.4 of the Policy. (3) The data used satisfies the data quantity requirements of Section 6.1.5 of the Policy. (4) The results of the nutrient analysis on the nitrogen, chlorophyll-a, and phosphorus samples show that there is no evidence that the bio-stimulatory narrative objective has been exceeded. The dissolved oxygen samples show that the lowest values sampled are still above the minimum objective. These results do not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. (5) Pursuant to Section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1663

Pollutant:

Nitrogen

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Measurement of nutrient species was planned because the Lost River is listed on the State 303(d) list for nutrients and this information is needed for system description. Ammonia, total Kjeldahl nitrogen (TKN), nitrate and nitrite were analytically determined. Total nitrogen was calculated from TKN, nitrate and nitrite. Total phosphorus and ortho-phosphate were analytically determined. The reasons for the recommendation to de-list the watershed include: There is no evidence that the biostimulatory narrative objective is exceeded. The system appears to be nitrogen limited and nitrogen levels are far below levels expected to cause biostimulation in this system. Although, phosphorus levels are elevated in comparison to U.S. EPA suggested levels, these suggested levels are not relevant because there is no evidence of excessive algal growth in the reservoir and the system appears to be nitrogen limited. Dissolved oxygen levels are above the existing numeric water quality objectives. The nitrogen levels are below the concentration of concern for human health. There is no evidence of impacts from nutrients, dissolved oxygen, or other nutrient related effects on the sensitive species of concern. The beneficial uses appear to be unaffected by water temperature. The natural range of water temperatures and nutrient concentrations above Clear Lake Reservoir do not appear to be affected by anthropogenic activities. The temperatures below Clear Lake Reservoir are affected by anthropogenic activities (i.e., the dam and water flow fluctuations) but these activities are not addressed by a TMDL (North Coast RWQCB, 2004d).
The Upper Lost River/Clear Lake Reservoir area is listed as impaired for nutrients and temperature in accordance with Section 303(d) of the federal Clean Water Act (CWA). The listing of the Upper Lost River/Clear Lake Reservoir watershed as impaired because of biostimulatory substances (nutrients) and high water temperature was made in 1996. In accordance with a consent decree, January 2005 is the deadline for adoption or de-listing of the TMDLs for the Upper Lost River/Clear Lake Reservoir area by the State of California. Investigation into the basis of the listings revealed that the listings were apparently conferred from the Klamath River listings and not based on data or information specific to the Upper Lost River and Clear Lake Reservoir watershed. The appropriateness of the nutrients and temperature listings in the Upper Lost River is explored in the TMDL analysis. If the listings had been confirmed a TMDL would have been developed, however, the listings were not confirmed and de-listing for the watershed (including Clear Lake Reservoir, the streams draining to Clear Lake Reservoir and the Upper Lost River between the Clear Lake Reservoir dam and the Oregon border) is recommended by the NCRWQCB staff.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Water shall not contain bio-stimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The WQO for Bio-stimulatory Substances is inclusive of nutrients.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1664

Pollutant:

Nitrogen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Nitrogen concentration was measured from monthly grab samples at the six sampling stations, for a total of 57 samples. The system appears to be nitrogen limited with nitrogen levels far below levels expected to cause bio-stimulation in this system. There is no evidence that the bio-stimulatory narrative is exceeded. The total nitrogen concentrations were similar between the two Upper Lost River stations and the four stations upstream of Clear Lake Reservoir. The total nitrogen concentrations are well below the 10 mg/l NO3-N set by the U.S. EPA (1986) to protect human health consuming domestic water supplies. In other words, the nitrogen levels are below the concentration of concern for human health.

The analytical laboratory measured ammonia, nitrate, nitrite and TKN. Total nitrogen was calculated from the sum of TKN, nitrate, and nitrite. The total nitrogen levels showed some variability ranging from below the analytical reporting limit of 0.05 mg/l to 1.85 mg/l. Of the 57 samples, 17 were below the analytical reporting limit. Since nitrogen was present in the system these were assumed to be half of the reporting limit for statistical analyses. The highest concentration of total nitrogen, 1.85 mg/l, consisted entirely of TKN (ammonia and organic nitrogen). It was from a sample taken in August 2002 at Boles Creek during a time when the creek had no surface flow. The median of all of the total nitrogen results was 0.69 mg/l, and the 95% upper confidence level was 0.77 mg/l.

The two stations on the Upper Lost River (WFLAT and LRCLDM) were analyzed separately from the four upstream stations on streams that drain to Clear Lake Reservoir (MOWCRK, BCFORD, WCGSB, and FCFORD). The 28 data points for the two Upper Lost River stations showed total nitrogen concentrations ranging from below the laboratory-reporting limit to 1.65 mg/l, with a median of 0.76 (including 8 non-detects assumed to be half of the reporting limit for statistical analysis purposes). The 29 points from the four stations on streams leading to Clear Lake Reservoir showed total nitrogen concentrations ranging from below the laboratory-reporting limit to 1.85 mg/l, with a median of 0.57 (including 10 non-detects assumed to be half of the reporting limit for statistical analysis purposes). Ammonia concentrations are low or below the laboratory reporting level at the six sampling stations.

Analysis of all six stations grouped together shows that of 57 samples, 37 were below the analytical reporting limit. If the non-detects are included at a concentration equal to half of the reporting limit, the median concentration of ammonia is 0.025 mg/l (the default level for the nondetect samples), and the range is from below the reporting limit to 0.23 mg/l NH4-N.

Separating the four upstream stations from the two Upper Lost River stations does not show a significant difference in ammonia concentrations. If the nondetects are included at a concentration equal to half of the laboratory reporting limit, both upstream stations and downstream stations have a median ammonia concentration of 0.025 NH4-N. There are several samples with ammonia concentrations below the laboratory-reporting limit (29 total samples with 17 non-detects in the upstream stations and 20 non-detects out of 28 total samples in the downstream sites), so analysis of these data is difficult. Calculations of the percentage of ammonia present as the toxic un-ionized ammonia were not necessary because the concentration of total ammonia at all of the stations is well below the level needed to protect the sensitive life stages of the sucker population (North Coast RWQCB, 2004d).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Water shall not contain bio-stimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The WQO for Bio-stimulatory substances includes Nitrogen. The USEPA concentration of 10 mg/l NO3-N set by the USEPA (1986) to protect human health consuming domestic water supplies.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Temporal Representation:

Sampling represents only one full season, late spring to early fall of one year. Sampling included monthly grab samples and instantaneous measurements for one season, continuous temperature monitoring for one season, and two short continuous multi-parameter deployments. The sampling periods do not correspond to the time periods that the suckers are in the streams. There were limited spots at which the streams could be accessed; these might not correspond to the points that provide representative data. Drawing conclusions about the impact of water temperature and nutrients on suckers based on sampling during summer, however, is justified because those months represent the conditions worse than the fish encounter during their time in the streams. Water temperature in the Upper Lost River/Clear Lake Reservoir watershed was investigated using: Remote continuous water and air temperature monitors (Optic stowaway data loggers) that took readings every 15 minutes from May through September 2002. Remote sensors that measured air temperature (Optic stowaway data loggers) and relative humidity (HOBO instruments) every 15 minutes for three days in June 2003. Solar pathfinder measurements to calculate solar radiation that reached stream surfaces. A thermal infrared aerial survey in July 2001and computer simulation modeling using the SSTEMP model. The monitoring instrument at the Boles Creek station was out of the water during that period due to seasonal dewatering and the sampling at Mowitz Creek did not begin until the following month.

Environmental Conditions:

QAPP Information:

NCRWQCB QA procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1659

Pollutant:

Nutrients

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Measurement of nutrient species was planned because the Lost River is listed on the State 303(d) list for nutrients and this information is needed for system description. Ammonia, total Kjeldahl nitrogen (TKN), nitrate and nitrite were analytically determined. Total nitrogen was calculated from TKN, nitrate and nitrite. Total phosphorus and ortho-phosphate were analytically determined. The reasons for the recommendation to de-list the watershed include: There is no evidence that the biostimulatory narrative objective is exceeded. The system appears to be nitrogen limited and nitrogen levels are far below levels expected to cause biostimulation in this system. Although, phosphorus levels are elevated in comparison to U.S. EPA suggested levels, these suggested levels are not relevant because there is no evidence of excessive algal growth in the reservoir (perhaps due to turbidity levels that control light availability) and the system appears to be nitrogen limited. Dissolved oxygen levels are above the existing numeric water quality objectives. The nitrogen levels are below the concentration of concern for human health. There is no evidence of impacts from nutrients, dissolved oxygen, or other nutrient related effects on the sensitive species of concern. The beneficial uses appear to be unaffected by water temperature. The natural range of water temperatures and nutrient concentrations above Clear Lake Reservoir do not appear to be affected by anthropogenic activities (North Coast RWQCB, 2004d).The Upper Lost River/Clear Lake Reservoir area is listed for nutrients and temperature in accordance with Section 303(d) of the federal Clean Water Act (CWA). The listing of the Upper Lost River/Clear Lake Reservoir watershed as impaired because of biostimulatory substances (nutrients) and high water temperature was made in 1996. In accordance with a consent decree, January 2005 is the deadline for adoption or de-listing of the TMDLs for the Upper Lost River/Clear Lake Reservoir area by the State of California. Investigation into the basis of the listings revealed that the listings were apparently conferred from the Klamath River listings and not based on data or information specific to the Upper Lost River and Clear Lake Reservoir watershed. The appropriateness of the nutrients and temperature listings in the Upper Lost River is explored in the TMDL analysis. If the listings had been confirmed a TMDL would have been developed, however, the listings were not confirmed and de-listing for the watershed (including Clear Lake Reservoir, the streams draining to Clear Lake Reservoir and the Upper Lost River between the Clear Lake Reservoir dam and the Oregon border) is recommended by the NCRWQCB staff.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Water shall not contain bio-stimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The WQO for Bio-stimulatory Substances is inclusive of nutrients for the NCRWQCB.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1660

Pollutant:

Nutrients

LOE Subgroup:

Pollutant-Nuisance

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The TMDL Analysis was completed for Upper Lost River and Clear Lake Reservoir Watershed. The Chlorophyll-a in the water column was measured from monthly grab samples at the six sampling stations, for a total of 57 samples. The water samples were filtered in the field, rinsed with magnesium carbonate, and preserved on dry ice because full-volume samples could not be delivered to analytical laboratory within the recommended holding period. The chlorophyll-a concentrations showed variability ranging from below the analytical reporting limit (0.00050 mg/l) to 0.016 mg/l. Of the 57 samples, 38 were below the analytical reporting limit; for statistical analyses, these concentrations were assumed to be half of the reporting limit. The high measurement, 0.016 mg/l, was from a sample taken in October 2002 at Mowitz Creek. The median of all of the chlorophyll-a results was 0.00025 mg/l (the default value for samples below the reporting limit), and the 95% upper confidence limit is 0.00174 mg/l. The two stations on the Upper Lost River (WFLAT and LRCLDM) were analyzed separately from the four upstream stations on streams that lead to Clear Lake Reservoir (MOWCRK, BCFORD, WCGSB, and FCFORD).

The 28 data points for the two Upper Lost River stations showed chlorophyll-a concentrations ranging from below the analytical reporting limit to 0.0032 mg/l, with a median of 0.00025 mg/l (the default value for samples below the reporting limit), and an 95% upper confidence limit of 0.00174 mg/l (including 21 nondetects assumed to be half of the reporting limit).

The 29 points from the four stations on streams leading to Clear Lake Reservoir showed chlorophyll-a concentrations ranging from below the laboratory reporting limit to 0.016 mg/l, with a median of 0.00025 mg/l (this is half of the laboratory reporting limit), and a 95% upper confidence level of 0.00279 mg/l. Although most of the data points in this dataset are nondetects (17 non-detects out of 29 data points), for the statistical analysis, they were assumed to be half of the reporting limit.

Using the 57 observations in the complete dataset, the relationship between total phosphorus and chlorophyll-a was weak. Neither visual observations nor water column chlorophyll-a measurements indicated impairment due to excess phosphorus. The lack of Chlorophyll-a in the water samples obtained for this analysis indicates that either the level of nutrients is too low to support excess algal growth or that some other factor is suppressing the algal growth. In either case, the beneficial uses of the Upper Lost River/Clear Lake Reservoir system are not impaired by nutrient concentrations (North Coast RWQCB, 2004d).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Water shall not contain bio-stimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The Bio-stimulatory WQO is inclusive of nutrients.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed for the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1666

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Specific WQOs in the Basin Plan Table 3.1.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

NCRQWQCB QA procedures followed for the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1665

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Continuous dissolved oxygen measurements made in the Upper Lost River at Walter Flat from September 30 to October 2, 2002.

Temporal Representation:

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1667

Pollutant:

Phosphorus

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Measurement of nutrient species was planned because the Lost River is listed on the State 303(d) list for nutrients and this information is needed for system description. Ammonia, total Kjeldahl nitrogen (TKN), nitrate and nitrite were analytically determined. Total nitrogen was calculated from TKN, nitrate and nitrite. Total phosphorus and ortho-phosphate were analytically determined. The reasons for the recommendation to de-list the watershed include: There is no evidence that the biostimulatory narrative objective is exceeded. The system appears to be nitrogen limited and nitrogen levels are far below levels expected to cause biostimulation in this system. Although, phosphorus levels are elevated in comparison to U.S. EPA suggested levels, these suggested levels are not relevant because there is no evidence of excessive algal growth in the reservoir (perhaps due to turbidity levels that control light availability) and the system appears to be nitrogen limited. Dissolved oxygen levels are above the existing numeric water quality objectives. The nitrogen levels are below the concentration of concern for human health. There is no evidence of impacts from nutrients, dissolved oxygen, or other nutrient related effects on the sensitive species of concern. The beneficial uses appear to be unaffected by water temperature. The natural range of water temperatures and nutrient concentrations above Clear Lake Reservoir do not appear to be affected by anthropogenic activities. The temperatures below Clear Lake Reservoir are affected by anthropogenic activities (i.e., the dam and water flow fluctuations) but these activities are not addressed by a TMDL (North Coast RWQCB, 2004d).The Upper Lost River/Clear Lake Reservoir area is listed for nutrients and temperature in accordance with Section 303(d) of the federal Clean Water Act (CWA). The listing of the Upper Lost River/Clear Lake Reservoir watershed as impaired because of biostimulatory substances (nutrients) and high water temperature was made in 1996. In accordance with a consent decree, January 2005 is the deadline for adoption or de-listing of the TMDLs for the Upper Lost River/Clear Lake Reservoir area by the State of California. Investigation into the basis of the listings revealed that the listings were apparently conferred from the Klamath River listings and not based on data or information specific to the Upper Lost River and Clear Lake Reservoir watershed. The appropriateness of the nutrients and temperature listings in the Upper Lost River is explored in the TMDL analysis. If the listings had been confirmed a TMDL would have been developed, however, the listings were not confirmed and de-listing for the watershed (including Clear Lake Reservoir, the streams draining to Clear Lake Reservoir and the Upper Lost River between the Clear Lake Reservoir dam and the Oregon border) is recommended by the NCRWQCB staff.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Water shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The WQO for Biostimulatory Substances is inclusive of nutrients.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed in the TMDL analysis.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68771, Nutrients	Region 1
Klamath River HU, Lost River HA, Clear Lake, Boles HSAs

LOE ID:

1668

Pollutant:

Phosphorus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The TMDL Analysis was completed for Upper Lost River and Clear Lake Reservoir Watershed. Total phosphorus was measured from monthly grab samples at the six sampling stations, for a total of 57 samples. The total phosphorus levels showed variability ranging from below the analytical reporting level to 4.5 mg/l. Of the 57 samples, 26 were below the analytical reporting limit; since phosphorus was present in the system these concentrations were assumed to be half of the reporting limit for statistical analyses. The high measurement, 4.5 mg/l, was from a sample taken in May 2002 at Fletcher Creek. The median of all of the total phosphorus results was 0.068 mg/l, and the 95% upper confidence limit is 0.35 mg/l, a level influenced by the abnormally high concentration at Fletcher Creek in May 2002.

The two stations on the Upper Lost River (WFLAT and LRCLDM) were analyzed separately from the four upstream stations on streams that drain to Clear Lake Reservoir (MOWCRK, BCFORD, WCGSB, and FCFORD). The 28 data points for the two Upper Lost River stations showed total phosphorus concentrations ranging from below the laboratory reporting limit to 0.37 mg/l, with a median of 0.20 mg/l, and a 95% upper confidence level of 0.23 mg/l (including four nondetects assumed to be half of the reporting limit). The 29 points from the four stations on streams leading to Clear Lake Reservoir showed total phosphorus concentrations ranging from below the laboratory-reporting limit to 4.5 mg/l, with a median of 0.025 mg/l (this is half of the laboratory reporting limit), and a 95% upper confidence level of 0.51 mg/l. Although most of the data points in this dataset are nondetects (22 nondetects out of 29 data points), for the complete dataset analysis, they were assumed to be half of the reporting limit. Total phosphorus levels were higher in the two downstream stations than in the stream stations upstream of Clear Lake Reservoir.

Median total phosphorus concentrations in the two Upper Lost River stations were above the 0.05-mg/l level suggested by the USEPA to control eutrophication in streams that enter lakes (USEPA 1986). Soil particles from discharged water from Clear Lake Reservoir may transport soil-organic-matter phosphorus and inorganic-soil/rock phosphorus to the Upper Lost River. The levels do not appear to present a eutrophication problem in the Upper Lost River or in Clear Lake Reservoir, probably because the high turbidity reduces sunlight penetration. The USBR (2000) indicated that there has been extensive siltation of Clear Lake Reservoir. Although, phosphorus levels are elevated in comparison to U.S. EPA suggested levels, these suggested levels are not relevant because there is no evidence of excessive algal growth in the reservoir (perhaps due to turbidity levels that control light availability) and the system appears to be nitrogen limited.

In the 57 observations in this dataset, the ratio between total nitrogen and total phosphorus ranged from 0 to 74. The value of R-Squared, the proportion of variation in total nitrogen that can be accounted for by variation in total phosphorus, is 0.0001; the correlation between total nitrogen and total phosphorus is -0.0097. There is no correlation between the values. These values are slightly different if the nitrogen nondetect values were reported as zero rather than half of the reporting limit. If the data sets with nondetects and the outlier are removed, there are 21 data points available for analysis of the nitrogen/phosphorus ratio. The N/P ratio for these points is shown in the third graph. A line showing an N/P of 10 is drawn for reference. Of the 21 data points, 18 have an N/P ratio of less than 10 this indicates
a system that is nitrogen limited (North Coast RWQCB, 2004d).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Basin Plan: Water shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

The WQO for Biostimulatory substances includes Phosphorus.
The USEPA phosphorus 0.05-mg/l level suggested by the USEPA to control eutrophication in streams that enter lakes (USEPA 1986).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

The monitoring locations for the Upper Lost River/Clear Lake Reservoir area are shown in Map 2 and are listed below with their station designations:
1. Lost River below Clear Lake Reservoir dam, LRCLDM.
2. Lost River at Walter Flat, WFLAT.
3. Mowitz Creek just downstream of the 136 bridge, MOWCRK.
4. Boles Creek just upstream of the 136 ford, BCFORD.
5. No. Fork Willow Creek below the Great Society Bridge, WCGSB.
6. Fletcher Creek just upstream of the 73 ford, FCFORD.

Two stations are on the Upper Lost River mainstem, one is downstream of the dam and the other at Walter Flat. Station LRCLDM is at a point about 1,000 meters downstream of Clear Lake Reservoir dam. Station WFLAT is at a point about 10 meters downstream of the Walter Flat Bridge, about eight miles downstream of the dam. In addition to the two stations on the Upper Lost River, there were four monitoring locations in streams that lead to Clear Lake Reservoir, the source of the Lost River. One station was on North Fork Willow Creek, the main tributary to Clear Lake Reservoir and the primary spawning stream for the endangered Lost River and shortnose suckers. Two other sites, on Boles and Fletcher Creeks, drain into Willow Creek. The fourth site, on Mowitz Creek, drains directly into Clear Lake Reservoir but does not contribute much water to the reservoir. This site was added late in the investigation because of the opportunity to add to a sparse dataset. All of the sites, except the station below the dam, were accessible only during late spring to early fall because wet weather made the roads impassable. Sampling locations were limited to areas that could be reached by truck. Logistical issues precluded sampling in Clear Lake Reservoir.

Temporal Representation:

Sampling represents only one full season, late spring to early fall of one year. Sampling included monthly grab samples and instantaneous measurements for one season, continuous temperature monitoring for one season, and two short continuous multiparameter deployments. The sampling periods do not correspond to the time periods that the suckers are in the streams. There were limited spots at which the streams could be accessed; these might not correspond to the points that provide representative data. Drawing conclusions about the impact of water temperature and nutrients on suckers based on sampling during summer is justified, because those months represent the conditions worse than the fish encounter during their time in the streams. Water temperature in the Upper Lost River/Clear Lake Reservoir watershed was investigated using: Remote continuous water and air temperature monitors (Optic stowaway dataloggers) that took readings every 15 minutes from May through September 2002. Remote sensors that measured air temperature (Optic stowaway dataloggers) and relative humidity (HOBO instruments) every 15 minutes for three days in June 2003. Solar pathfinder measurements to calculate solar radiation that reached stream surfaces. A thermal infrared aerial survey in July 2001and computer simulation modeling using the SSTEMP model. The monitoring instrument at the Boles Creek station was out of the water during that period due to seasonal dewatering and the sampling at Mowitz Creek did not begin until the following month.

Environmental Conditions:

QAPP Information:

NCRWQCB QA Procedures followed for the TMDL analysis.

QAPP Information Reference(s):