Final California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name: Guadalupe River
Water Body ID: CAR2054005019980928160437
Water Body Type: River & Stream
 
DECISION ID
141990
Region 2     
Guadalupe River
 
Pollutant: Diazinon
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status Revised
Sources: A Source Unknown | Other Urban Runoff | Surface Runoff
TMDL Name: San Francisco Bay Urban Creeks Diazinon
TMDL Project Code: 9
Date TMDL Approved by USEPA: 05/16/2007
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A product ban for urban uses of diazinon in 1999 which has caused dramatic reduction in use.
4. Zero of four recent sediment samples (since the ban) exceeded the evaluation guideline.
5. However, there are not a sufficient number of water samples to de-list this waterbody according to Table 4.1 of the Listing Policy.
6. The Pesticides in Urban Creeks TMDL was approved by USEPA on 5/21/2007.
7. 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 not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141990, Diazinon
Region 2     
Guadalupe River
 
LOE ID: 272460
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al., (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2013-06-26
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141990, Diazinon
Region 2     
Guadalupe River
 
LOE ID: 272462
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al., (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2013-06-26
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141990, Diazinon
Region 2     
Guadalupe River
 
LOE ID: 91868
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141990, Diazinon
Region 2     
Guadalupe River
 
LOE ID: 91869
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141990, Diazinon
Region 2     
Guadalupe River
 
LOE ID: 1805
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified---This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
 
DECISION ID
145439
Region 2     
Guadalupe River
 
Pollutant: Mercury
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status Revised
Sources: A Source Unknown
TMDL Name: Guadalupe River Watershed Mercury
TMDL Project Code: 11
Date TMDL Approved by USEPA: 06/01/2010
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under section 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Eight lines of evidence are available in the administrative record to assess this pollutant.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of seven samples exceeded the sediment mercury evaluation guideline and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy. There are no corresponding toxicity data to complement the sediment mercury data, but there are data showing evidence of exceeding water quality objectives prior to 2006.
4. The Guadalupe River Watershed Mercury TMDL was approved by USEPA on 6/1/2010.
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: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
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 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 91831
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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. Region 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. . For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 205GUA020.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 3751
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Not Recorded
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference pre-2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 269082
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 274367
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 4 of the 6 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for mercury is the probable effect concentration (PEC) of 1.06 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 274513
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 4 of the 6 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for mercury is the probable effect concentration (PEC) of 1.06 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 91886
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Mercury.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 145439, Mercury
Region 2     
Guadalupe River
 
LOE ID: 91887
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Mercury.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for mercury is 1.06 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142000
Region 2     
Guadalupe River
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142000, 2,4-D (2,4-Dichlorophenoxy acetic acid)
Region 2     
Guadalupe River
 
LOE ID: 283527
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for dichlorophenoxyacetic acid, 2,4- (2,4-D) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142000, 2,4-D (2,4-Dichlorophenoxy acetic acid)
Region 2     
Guadalupe River
 
LOE ID: 283528
 
Pollutant: 2,4-D (2,4-Dichlorophenoxy acetic acid)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dichlorophenoxyacetic Acid, 2,4-.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for dichlorophenoxyacetic acid, 2,4- (2,4-D) is the USEPA Aquatic Life Benchmark of 299.2 ug/L for a vascular plant (acute).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
142014
Region 2     
Guadalupe River
 
Pollutant: 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142014, 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
Region 2     
Guadalupe River
 
LOE ID: 284141
 
Pollutant: 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for MCPA.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for 2-methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid is the USEPA Aquatic Life Benchmark of 20 ug/L for a vascular plant (acute) for MCPA EHE.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142014, 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
Region 2     
Guadalupe River
 
LOE ID: 284165
 
Pollutant: 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for MCPA.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for 2-methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid is the USEPA Aquatic Life Benchmark of 20 ug/L for a vascular plant (acute) for MCPA EHE.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
142018
Region 2     
Guadalupe River
 
Pollutant: Alkalinity as CaCO3
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277406
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277229
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River 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: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277249
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277407
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277487
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277266
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River 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: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277250
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River 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: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277248
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277065
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277048
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277230
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River 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: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142018, Alkalinity as CaCO3
Region 2     
Guadalupe River
 
LOE ID: 277049
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
150940
Region 2     
Guadalupe River
 
Pollutant: Ammonia
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279378
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279277
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279507
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279611
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279162
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279379
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279160
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278852
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279674
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279104
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279532
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279359
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279158
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 279279
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.20 Un-Ionized Ammonia: The discharge of wastes shall not cause receiving waters to contain concentrations of un-ionized ammonia in excess 0.025 mg/l (as N), expressed as an annual median.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278383
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278396
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278235
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River 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: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 277887
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 277888
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River 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: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278063
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 277864
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 277880
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 277786
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River 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: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278062
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278044
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River 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: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278043
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278213
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150940, Ammonia
Region 2     
Guadalupe River
 
LOE ID: 278336
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River 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: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
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: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
141977
Region 2     
Guadalupe River
 
Pollutant: Anthracene
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 141977, Anthracene
Region 2     
Guadalupe River
 
LOE ID: 91800
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Anthracene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for anthracene is 845 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141977, Anthracene
Region 2     
Guadalupe River
 
LOE ID: 91799
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Anthracene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for anthracene is 845 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141977, Anthracene
Region 2     
Guadalupe River
 
LOE ID: 269612
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for anthracene is the probable effect concentration (PEC) of 845 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141977, Anthracene
Region 2     
Guadalupe River
 
LOE ID: 269677
 
Pollutant: Anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Anthracene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for anthracene is the probable effect concentration (PEC) of 845 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141979
Region 2     
Guadalupe River
 
Pollutant: Arsenic
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 141979, Arsenic
Region 2     
Guadalupe River
 
LOE ID: 91772
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141979, Arsenic
Region 2     
Guadalupe River
 
LOE ID: 91801
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Arsenic.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for arsenic is 33 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141979, Arsenic
Region 2     
Guadalupe River
 
LOE ID: 269627
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for arsenic is the probable effect concentration (PEC) of 33 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141979, Arsenic
Region 2     
Guadalupe River
 
LOE ID: 269785
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for arsenic is the probable effect concentration (PEC) of 33 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
154157
Region 2     
Guadalupe River
 
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 section 3.9 of the Listing Policy. Under section 3.9, when data show benthic community degradation and there is at least one pollutant impairment that could impact benthic macroinvertebrates, the waterbody is placed on the 303(d) List for benthic community effects.

Seven lines of evidence evaluating benthic macroinvertebrate bioassessment data are available in the administrative record to assess this indicator. Seven of seven benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold of 0.79. At least one line of evidence includes sufficient pollutant exceedances to indicate the waterbody is impaired for at least one pollutant. However, there is insufficient data and/or information to determine if at least one pollutant could be impacting benthic macroinvertebrates.

Based on the readily available data and information, the evidence indicates that there is sufficient justification against placing Benthic Community Effects in this waterbody segment on the CWA section 303(d) List. Although there is insufficient data and/or information to make a beneficial use support determination, the exceedances of the benthic macroinvertebrate samples indicate beneficial uses may be potentially threatened.

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. Seven of seven benthic macroinvertebrate bioassessment samples had CSCI scores below 0.79.
4. At least one line of evidence includes sufficient pollutant exceedances to indicate the waterbody is impaired for at least one pollutant related to aquatic life; however, data and/or information are insufficient to determine if the pollutant(s) is impacting benthic macroinvertebrates.
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: 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 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306461
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205R01114 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.392056 to 0.392056.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205R01114.
Temporal Representation: Samples were collected from 5/3/2016 to 5/3/2016.
Environmental Conditions:
QAPP Information: Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306450
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205R00259 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.438242 to 0.438242.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205R00259.
Temporal Representation: Samples were collected from 6/14/2012 to 6/14/2012.
Environmental Conditions:
QAPP Information: Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 275744
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 9 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 90712
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 1 of 1 samples collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the San Francisco Bay Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected on 6/17/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 270945
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlordane is the probable effect concentration (PEC) of 17.6 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 280601
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Bifenthrin. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
 
Spatial Representation: The samples were collected at 1 monitoring site (Santa Clara 27).
Temporal Representation: Data for this waterbody was collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 270221
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 2 of the 9 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306460
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205R00346 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.4775 to 0.4775.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205R00346.
Temporal Representation: Samples were collected from 6/14/2012 to 6/14/2012.
Environmental Conditions:
QAPP Information: Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306449
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205PS0109 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.684430292 to 0.684430292.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205PS0109.
Temporal Representation: Samples were collected from 6/21/2011 to 6/21/2011.
Environmental Conditions:
QAPP Information: Data were collected using Surface Water Ambient Monitoring Program protocols
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306484
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205R00771 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.505685 to 0.505685.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205R00771.
Temporal Representation: Samples were collected from 6/6/2013 to 6/6/2013.
Environmental Conditions:
QAPP Information: Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306485
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205R01027 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.520797 to 0.520797.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205R01027.
Temporal Representation: Samples were collected from 5/5/2014 to 5/5/2014.
Environmental Conditions:
QAPP Information: Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 154157, Benthic Community Effects
Region 2     
Guadalupe River
 
LOE ID: 306486
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 205R02051 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.319006 to 0.319006.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce significant alterations in population or community ecology or receiving water biota. In addition, the health and life history characteristics of aquatic organisms in waters affected by controllable water quality factors shall not differ significantly from those for the same waters in areas unaffected by controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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 (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use. 
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 205R02051.
Temporal Representation: Samples were collected from 5/19/2015 to 5/19/2015.
Environmental Conditions:
QAPP Information: Data were collected according to BASMAA Regional Monitoring Coalition sampling protocols.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
141981
Region 2     
Guadalupe River
 
Pollutant: Benzo(a)anthracene
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 141981, Benzo(a)anthracene
Region 2     
Guadalupe River
 
LOE ID: 269889
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for benz[a]anthrazene is the probable effect concentration (PEC) of 1050 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141981, Benzo(a)anthracene
Region 2     
Guadalupe River
 
LOE ID: 91773
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)anthracene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141981, Benzo(a)anthracene
Region 2     
Guadalupe River
 
LOE ID: 91774
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)anthracene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for Benzo(a)anthracene is 1050 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141981, Benzo(a)anthracene
Region 2     
Guadalupe River
 
LOE ID: 269986
 
Pollutant: Benzo(a)anthracene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Benz(a)anthracene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for benz[a]anthrazene is the probable effect concentration (PEC) of 1050 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141980
Region 2     
Guadalupe River
 
Pollutant: Benzo(a)pyrene
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 141980, Benzo(a)pyrene
Region 2     
Guadalupe River
 
LOE ID: 270175
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for benzo[a]pyrene is the probable effect concentration (PEC) of 1450 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141980, Benzo(a)pyrene
Region 2     
Guadalupe River
 
LOE ID: 91775
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)pyrene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141980, Benzo(a)pyrene
Region 2     
Guadalupe River
 
LOE ID: 91776
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Benzo(a)pyrene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Benzo(a)Pyrene is 1450 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141980, Benzo(a)pyrene
Region 2     
Guadalupe River
 
LOE ID: 270207
 
Pollutant: Benzo(a)pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Benzo(a)pyrene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for benzo[a]pyrene is the probable effect concentration (PEC) of 1450 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141982
Region 2     
Guadalupe River
 
Pollutant: Cadmium
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 141982, Cadmium
Region 2     
Guadalupe River
 
LOE ID: 270502
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cadmium is the probable effect concentration (PEC) of 4.98 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141982, Cadmium
Region 2     
Guadalupe River
 
LOE ID: 91780
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141982, Cadmium
Region 2     
Guadalupe River
 
LOE ID: 91779
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cadmium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for cadmium is 4.98 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141982, Cadmium
Region 2     
Guadalupe River
 
LOE ID: 270506
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cadmium is the probable effect concentration (PEC) of 4.98 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141984
Region 2     
Guadalupe River
 
Pollutant: Chloride
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281361
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed EPA National Lakes Assessment 2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205L12145 (Los Alamitos Percolation Ponds).
Temporal Representation: The samples were collected between the dates of 2012-07-30 and 2012-07-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281508
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281291
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281292
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281044
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281378
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281729
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281079
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281078
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281566
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281000
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281567
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281507
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed EPA National Lakes Assessment 2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205L12145 (Los Alamitos Percolation Ponds).
Temporal Representation: The samples were collected between the dates of 2012-07-30 and 2012-07-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281077
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281289
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141984, Chloride
Region 2     
Guadalupe River
 
LOE ID: 281045
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chloride.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
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: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
141985
Region 2     
Guadalupe River
 
Pollutant: Chlorine
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.

Although there was a sufficient number of samples to assess total chlorine, this water body was given a use rating of Insufficient Information and a Do Not List decision. First, data were collected with field instruments that do not have the sensitivity to detect low levels of total chlorine to assess the freshwater water quality objectives of 11 ug/L and 19 ug/L. Secondly, most of the data were collected only once for a given site, and the data were not collected with the purpose of assessing chlorine levels in the water body. A more appropriate sampling to determine water quality impacts of chlorine might be conducted for future Integrated Report assessments.
 
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 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 281928
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282544
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282210
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282601
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282124
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282005
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282191
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282087
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282032
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282645
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282841
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 141985, Chlorine
Region 2     
Guadalupe River
 
LOE ID: 282685
 
Pollutant: Chlorine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorine, Total Residual.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The USEPA recommended chlorine criterion for the protection of aquatic ife in freshwater is 11 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
141986
Region 2     
Guadalupe River
 
Pollutant: Chlorophyll-a
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 141986, Chlorophyll-a
Region 2     
Guadalupe River
 
LOE ID: 282992
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed EPA National Lakes Assessment 2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorophyll a.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A – Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife).Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: The samples were collected at 1 monitoring site: 205L12145 (Los Alamitos Percolation Ponds).
Temporal Representation: The samples were collected between the dates of 2012-07-30 and 2012-07-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141986, Chlorophyll-a
Region 2     
Guadalupe River
 
LOE ID: 282928
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed EPA National Lakes Assessment 2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chlorophyll a.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A – Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife).Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: The samples were collected at 1 monitoring site: 205L12145 (Los Alamitos Percolation Ponds).
Temporal Representation: The samples were collected between the dates of 2012-07-30 and 2012-07-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141987
Region 2     
Guadalupe River
 
Pollutant: Chlorpyrifos
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 141987, Chlorpyrifos
Region 2     
Guadalupe River
 
LOE ID: 91782
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141987, Chlorpyrifos
Region 2     
Guadalupe River
 
LOE ID: 270796
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2017-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141987, Chlorpyrifos
Region 2     
Guadalupe River
 
LOE ID: 271032
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2017-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141987, Chlorpyrifos
Region 2     
Guadalupe River
 
LOE ID: 91781
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142022
Region 2     
Guadalupe River
 
Pollutant: Chromium
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 CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

7 lines of evidence are available in the administrative record to assess this pollutant. 7 of the 7 sediment samples exceed the evaluation guideline. 3 total samples exceeded both sediment and toxicity. However, deep sediment cores from San Francisco Bay (Hornberger 1999) suggest that background chromium concentrations are larger than the evaluation guideline due to natural geologic formations high in chromium. In fact, nearly all of the sediment chromium concentrations are less than the estimated background concentration of about 113 to 143 ug/kg. Moreover, the association between chromium and sediment toxicity is not certain in that the high chromium concentration in the data set did not have associated sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is NOT SUFFICIENT justification FOR 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. 3 of the 3 samples exceed the evaluation guideline for both sediment and sediment toxicity.
4. Although chromium in sediment exceeded the probable effect concentration, there is insufficient information to justify adding that pollutant to the CWA section 303(d) List. Chromium is high in the geologic formations (e.g., serpentinite) in the Bay Area. Hornberger et al., (1999) reported chromium concentrations ranging from 113-143 mg/kg in Bay sediment cores. The natural background in San Francisco Bay is on average substantially higher than the chromium sediment evaluation guideline. Therefore, chromium exceedances for sediment in this watershed are likely due to geologic conditions and not from an anthropogenic source.

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: 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 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 91783
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 91784
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chromium.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for chromium is 111 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 270837
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 270855
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 269082
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142022, Chromium
Region 2     
Guadalupe River
 
LOE ID: 91831
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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. Region 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. . For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 205GUA020.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
 
DECISION ID
141988
Region 2     
Guadalupe River
 
Pollutant: Chrysene (C1-C4)
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141988, Chrysene (C1-C4)
Region 2     
Guadalupe River
 
LOE ID: 271254
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chrysene is the probable effect concentration (PEC) of 1290 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141988, Chrysene (C1-C4)
Region 2     
Guadalupe River
 
LOE ID: 91785
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chrysene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Chrysene is 1290 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141988, Chrysene (C1-C4)
Region 2     
Guadalupe River
 
LOE ID: 91786
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Chrysene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Chrysene is 1290 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141988, Chrysene (C1-C4)
Region 2     
Guadalupe River
 
LOE ID: 271273
 
Pollutant: Chrysene (C1-C4)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Chrysene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chrysene is the probable effect concentration (PEC) of 1290 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141989
Region 2     
Guadalupe River
 
Pollutant: Copper
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141989, Copper
Region 2     
Guadalupe River
 
LOE ID: 91788
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141989, Copper
Region 2     
Guadalupe River
 
LOE ID: 271083
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for copper is the probable effect concentration (PEC) of 149 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141989, Copper
Region 2     
Guadalupe River
 
LOE ID: 271606
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for copper is the probable effect concentration (PEC) of 149 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141989, Copper
Region 2     
Guadalupe River
 
LOE ID: 91787
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Copper.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for copper is 149 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142019
Region 2     
Guadalupe River
 
Pollutant: Cyfluthrin
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 142019, Cyfluthrin
Region 2     
Guadalupe River
 
LOE ID: 91790
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyfluthrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142019, Cyfluthrin
Region 2     
Guadalupe River
 
LOE ID: 91789
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyfluthrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142019, Cyfluthrin
Region 2     
Guadalupe River
 
LOE ID: 283377
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cyfluthrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142019, Cyfluthrin
Region 2     
Guadalupe River
 
LOE ID: 271800
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142019, Cyfluthrin
Region 2     
Guadalupe River
 
LOE ID: 283442
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cyfluthrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142019, Cyfluthrin
Region 2     
Guadalupe River
 
LOE ID: 271885
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142021
Region 2     
Guadalupe River
 
Pollutant: Cyhalothrin, Lambda
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 142021, Cyhalothrin, Lambda
Region 2     
Guadalupe River
 
LOE ID: 271971
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142021, Cyhalothrin, Lambda
Region 2     
Guadalupe River
 
LOE ID: 284111
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142021, Cyhalothrin, Lambda
Region 2     
Guadalupe River
 
LOE ID: 284403
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142021, Cyhalothrin, Lambda
Region 2     
Guadalupe River
 
LOE ID: 271718
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142021, Cyhalothrin, Lambda
Region 2     
Guadalupe River
 
LOE ID: 91791
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyhalothrin, lambda, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142021, Cyhalothrin, Lambda
Region 2     
Guadalupe River
 
LOE ID: 91857
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyhalothrin, lambda, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142016
Region 2     
Guadalupe River
 
Pollutant: Cypermethrin
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 142016, Cypermethrin
Region 2     
Guadalupe River
 
LOE ID: 91858
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cypermethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142016, Cypermethrin
Region 2     
Guadalupe River
 
LOE ID: 91859
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cypermethrin, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142016, Cypermethrin
Region 2     
Guadalupe River
 
LOE ID: 283556
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142016, Cypermethrin
Region 2     
Guadalupe River
 
LOE ID: 272113
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 1 of the 9 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al., (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142016, Cypermethrin
Region 2     
Guadalupe River
 
LOE ID: 283160
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142016, Cypermethrin
Region 2     
Guadalupe River
 
LOE ID: 272288
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 1 of the 9 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al., (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
145723
Region 2     
Guadalupe River
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 145723, DDD (Dichlorodiphenyldichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 272272
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the sum of DDD is the probable effect concentration (PEC) of 28 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 145723, DDD (Dichlorodiphenyldichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 272119
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the sum of DDD is the probable effect concentration (PEC) of 28 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 145723, DDD (Dichlorodiphenyldichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 91860
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDD is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 145723, DDD (Dichlorodiphenyldichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 91861
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDD is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
148173
Region 2     
Guadalupe River
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 148173, DDE (Dichlorodiphenyldichloroethylene)
Region 2     
Guadalupe River
 
LOE ID: 91863
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148173, DDE (Dichlorodiphenyldichloroethylene)
Region 2     
Guadalupe River
 
LOE ID: 91862
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148173, DDE (Dichlorodiphenyldichloroethylene)
Region 2     
Guadalupe River
 
LOE ID: 272261
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the sum of DDE is the probable effect concentration (PEC) of 31.3 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 148173, DDE (Dichlorodiphenyldichloroethylene)
Region 2     
Guadalupe River
 
LOE ID: 272083
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the sum of DDE is the probable effect concentration (PEC) of 31.3 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
148256
Region 2     
Guadalupe River
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
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 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 272488
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the sum of DDT is the probable effect concentration (PEC) of 62.9 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 91829
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for total DDTs is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 91830
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for total DDTs is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 91864
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 91865
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 272410
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the sum of DDT is the probable effect concentration (PEC) of 62.9 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 276116
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for total DDTs is the probable effect concentration (PEC) of 572 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 148256, DDT (Dichlorodiphenyltrichloroethane)
Region 2     
Guadalupe River
 
LOE ID: 276299
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for total DDTs is the probable effect concentration (PEC) of 572 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142020
Region 2     
Guadalupe River
 
Pollutant: Deltamethrin
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 142020, Deltamethrin
Region 2     
Guadalupe River
 
LOE ID: 91867
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Deltamethrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142020, Deltamethrin
Region 2     
Guadalupe River
 
LOE ID: 91866
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Deltamethrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142020, Deltamethrin
Region 2     
Guadalupe River
 
LOE ID: 283758
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142020, Deltamethrin
Region 2     
Guadalupe River
 
LOE ID: 283756
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142020, Deltamethrin
Region 2     
Guadalupe River
 
LOE ID: 272494
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2017-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142020, Deltamethrin
Region 2     
Guadalupe River
 
LOE ID: 272335
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2017-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142012
Region 2     
Guadalupe River
 
Pollutant: Dicamba
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142012, Dicamba
Region 2     
Guadalupe River
 
LOE ID: 283721
 
Pollutant: Dicamba
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dicamba.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for dicamba is the USEPA Aquatic Life Benchmark of 61 ug/L for a nonvascular plant (acute) for Dicamba acid.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142012, Dicamba
Region 2     
Guadalupe River
 
LOE ID: 283680
 
Pollutant: Dicamba
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Dicamba.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for dicamba is the USEPA Aquatic Life Benchmark of 61 ug/L for a nonvascular plant (acute) for Dicamba acid.
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
141991
Region 2     
Guadalupe River
 
Pollutant: Dieldrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141991, Dieldrin
Region 2     
Guadalupe River
 
LOE ID: 91871
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141991, Dieldrin
Region 2     
Guadalupe River
 
LOE ID: 91870
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141991, Dieldrin
Region 2     
Guadalupe River
 
LOE ID: 272914
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for dieldrin is the probable effect concentration (PEC) of 61.8 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141991, Dieldrin
Region 2     
Guadalupe River
 
LOE ID: 272908
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for dieldrin is the probable effect concentration (PEC) of 61.8 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141992
Region 2     
Guadalupe River
 
Pollutant: Endrin
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 141992, Endrin
Region 2     
Guadalupe River
 
LOE ID: 91873
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141992, Endrin
Region 2     
Guadalupe River
 
LOE ID: 91872
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141992, Endrin
Region 2     
Guadalupe River
 
LOE ID: 272964
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for endrin is the probable effect concentration (PEC) of 207 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141992, Endrin
Region 2     
Guadalupe River
 
LOE ID: 272658
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for endrin is the probable effect concentration (PEC) of 207 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142024
Region 2     
Guadalupe River
 
Pollutant: Esfenvalerate/Fenvalerate
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142024, Esfenvalerate/Fenvalerate
Region 2     
Guadalupe River
 
LOE ID: 91875
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142024, Esfenvalerate/Fenvalerate
Region 2     
Guadalupe River
 
LOE ID: 91874
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate, total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142024, Esfenvalerate/Fenvalerate
Region 2     
Guadalupe River
 
LOE ID: 273200
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2016-07-14
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142024, Esfenvalerate/Fenvalerate
Region 2     
Guadalupe River
 
LOE ID: 273283
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2016-07-14
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142023
Region 2     
Guadalupe River
 
Pollutant: Fenpropathrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142023, Fenpropathrin
Region 2     
Guadalupe River
 
LOE ID: 273079
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 8 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al., ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142023, Fenpropathrin
Region 2     
Guadalupe River
 
LOE ID: 273099
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 8 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al., ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142023, Fenpropathrin
Region 2     
Guadalupe River
 
LOE ID: 91876
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fenpropathrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142023, Fenpropathrin
Region 2     
Guadalupe River
 
LOE ID: 91877
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fenpropathrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142011
Region 2     
Guadalupe River
 
Pollutant: Fipronil
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142011, Fipronil
Region 2     
Guadalupe River
 
LOE ID: 273207
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-25 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142011, Fipronil
Region 2     
Guadalupe River
 
LOE ID: 283978
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fipronil. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142011, Fipronil
Region 2     
Guadalupe River
 
LOE ID: 283957
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fipronil. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the four-day average concentration of fipronil does not exceed 0.0032 ug/L (3.2 ng/L) in the water column more than once every three years on average (Bower, et al. 2017).
Guideline Reference: Water and Sediment Quality Criteria Report for Fipronil. Phase III: Application of the pesticide water and sediment quality criteria methodologies. Department of Environmental Toxicology, University of California, Davis.
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142011, Fipronil
Region 2     
Guadalupe River
 
LOE ID: 273138
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Fipronil .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-25 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141978
Region 2     
Guadalupe River
 
Pollutant: Fipronil Desulfinyl
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141978, Fipronil Desulfinyl
Region 2     
Guadalupe River
 
LOE ID: 283821
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 141978, Fipronil Desulfinyl
Region 2     
Guadalupe River
 
LOE ID: 283820
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
142025
Region 2     
Guadalupe River
 
Pollutant: Fipronil Sulfide
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142025, Fipronil Sulfide
Region 2     
Guadalupe River
 
LOE ID: 283983
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fipronil Sulfide.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil sulfide is the USEPA Aquatic Life Benchmark of 0.83 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142025, Fipronil Sulfide
Region 2     
Guadalupe River
 
LOE ID: 273010
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-25 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142025, Fipronil Sulfide
Region 2     
Guadalupe River
 
LOE ID: 283922
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fipronil Sulfide.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil sulfide is the USEPA Aquatic Life Benchmark of 0.83 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142025, Fipronil Sulfide
Region 2     
Guadalupe River
 
LOE ID: 273012
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Fipronil Sulfide .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-25 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142026
Region 2     
Guadalupe River
 
Pollutant: Fipronil Sulfone
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142026, Fipronil Sulfone
Region 2     
Guadalupe River
 
LOE ID: 273391
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-25 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142026, Fipronil Sulfone
Region 2     
Guadalupe River
 
LOE ID: 284067
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fipronil Sulfone.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142026, Fipronil Sulfone
Region 2     
Guadalupe River
 
LOE ID: 273294
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Fipronil Sulfone .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al., 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-25 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142026, Fipronil Sulfone
Region 2     
Guadalupe River
 
LOE ID: 284050
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for Fipronil Sulfone.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
141993
Region 2     
Guadalupe River
 
Pollutant: Fluoranthene
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 141993, Fluoranthene
Region 2     
Guadalupe River
 
LOE ID: 91879
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluoranthene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Fluoranthene is 2,230 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141993, Fluoranthene
Region 2     
Guadalupe River
 
LOE ID: 91878
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluoranthene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Fluoranthene is 2,230 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141993, Fluoranthene
Region 2     
Guadalupe River
 
LOE ID: 273543
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fluoranthene is the probable effect concentration (PEC) of 2230 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141993, Fluoranthene
Region 2     
Guadalupe River
 
LOE ID: 273535
 
Pollutant: Fluoranthene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Fluoranthene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fluoranthene is the probable effect concentration (PEC) of 2230 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141994
Region 2     
Guadalupe River
 
Pollutant: Fluorene
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 141994, Fluorene
Region 2     
Guadalupe River
 
LOE ID: 91881
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluorene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for fluorene is 536 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141994, Fluorene
Region 2     
Guadalupe River
 
LOE ID: 91880
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fluorene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for fluorene is 536 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141994, Fluorene
Region 2     
Guadalupe River
 
LOE ID: 273670
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fluorene is the probable effect concentration (PEC) for Fluorene is 536 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141994, Fluorene
Region 2     
Guadalupe River
 
LOE ID: 273464
 
Pollutant: Fluorene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Fluorene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for fluorene is the probable effect concentration (PEC) for Fluorene is 536 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142013
Region 2     
Guadalupe River
 
Pollutant: Imidacloprid
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 142013, Imidacloprid
Region 2     
Guadalupe River
 
LOE ID: 283933
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Imidacloprid. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of imidacloprid does not exceed 0.016 ug/L.
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142013, Imidacloprid
Region 2     
Guadalupe River
 
LOE ID: 283954
 
Pollutant: Imidacloprid
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Imidacloprid. Although a total of 2 samples were collected, 2 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: UC Davis Aquatic Life Criteria: Aquatic life should not be affected unacceptably if the 4-day average concentration of imidacloprid does not exceed 0.016 ug/L.
Guideline Reference: Water Quality Criteria Report for Imidacloprid Phase III: Application of the pesticide water quality criteria methodology. Department of Environmental Toxicology. University of California, Davis
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
141995
Region 2     
Guadalupe River
 
Pollutant: Lead
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 CWA section 303(d) List under section 3.1 of the Listing Policy.

Zero samples exceeded the objectives, guidelines, or criteria for beneficial uses applicable to this water segment-pollutant combination, which is less than the minimum number of exceedances needed to place the water segment on the section CWA section 303(d) List for toxicants (Table 3.1 of the Listing Policy).

The data used satisfies the data quality requirements (section 6.1.4) and data quantity requirements (section 6.1.5) of the Listing Policy.

Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. 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.
 
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 141995, Lead
Region 2     
Guadalupe River
 
LOE ID: 91883
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141995, Lead
Region 2     
Guadalupe River
 
LOE ID: 91882
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Lead.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for lead is 128 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141995, Lead
Region 2     
Guadalupe River
 
LOE ID: 274138
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lead is the probable effect concentration (PEC) of 128 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141995, Lead
Region 2     
Guadalupe River
 
LOE ID: 273998
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lead is the probable effect concentration (PEC) of 128 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141996
Region 2     
Guadalupe River
 
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: 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141996, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 2     
Guadalupe River
 
LOE ID: 91885
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141996, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 2     
Guadalupe River
 
LOE ID: 91884
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141996, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 2     
Guadalupe River
 
LOE ID: 273826
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 5 samples were collected, 2 of these samples were not included 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 Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lindane is the probable effect concentration (PEC) for Lindane is 4.99 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141996, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 2     
Guadalupe River
 
LOE ID: 273842
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 5 samples were collected, 2 of these samples were not included 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 Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for lindane is the probable effect concentration (PEC) for Lindane is 4.99 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
141997
Region 2     
Guadalupe River
 
Pollutant: Methyl Parathion
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141997, Methyl Parathion
Region 2     
Guadalupe River
 
LOE ID: 91889
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Parathion, Methyl.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141997, Methyl Parathion
Region 2     
Guadalupe River
 
LOE ID: 274975
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al., (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2013-06-26
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141997, Methyl Parathion
Region 2     
Guadalupe River
 
LOE ID: 274993
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 3 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al., (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2013-06-26
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141997, Methyl Parathion
Region 2     
Guadalupe River
 
LOE ID: 91888
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Parathion, Methyl.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al. (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
141998
Region 2     
Guadalupe River
 
Pollutant: Naphthalene
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 141998, Naphthalene
Region 2     
Guadalupe River
 
LOE ID: 91891
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Naphthalene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for naphthalene is 561 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141998, Naphthalene
Region 2     
Guadalupe River
 
LOE ID: 274658
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for naphthalene is the probable effect concentration (PEC) of 561 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141998, Naphthalene
Region 2     
Guadalupe River
 
LOE ID: 274593
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Naphthalene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for naphthalene is the probable effect concentration (PEC) of 561 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141998, Naphthalene
Region 2     
Guadalupe River
 
LOE ID: 91890
 
Pollutant: Naphthalene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Naphthalene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for naphthalene is 561 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
141999
Region 2     
Guadalupe River
 
Pollutant: Nickel
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 CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.
Four lines of evidence are available in the administrative record to assess this pollutant. 7 of the 7 samples exceed the evaluation guideline. However, background nickel concentrations in the Guadalupe River watershed are higher than the evaluation guideline due to natural geologic formations. Toxicity data were not associated with this decision.
Based on the readily available data and information, the weight of evidence indicates that there is INSUFFICIENT justification for placing this water segment-pollutant combination on the CWA section 303(d) List.
This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 7 of the 7 samples exceed the evaluation guideline and this sample size is SUFFICIENT to determine beneficial use support, with the power and confidence of the Listing Policy. Although nickel in sediment exceeded the probable effect concentration, there is insufficient information to justify adding that pollutant to the CWA section 303(d) List. Nickel is high in the geologic formations (e.g., serpentinite) in the Bay Area. Hornberger et al., (1999) reported nickel concentrations ranging from 70-200 mg/kg in Bay sediment cores. The natural background in San Francisco Bay is on average more than double the nickel sediment evaluation guideline. Therefore, nickel exceedances for sediment in the Guadalupe River watershed is likely due to geologic conditions and not from an anthropogenic source.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141999, Nickel
Region 2     
Guadalupe River
 
LOE ID: 91892
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141999, Nickel
Region 2     
Guadalupe River
 
LOE ID: 274704
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for nickel is the probable effect concentration (PEC) of 48.6 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141999, Nickel
Region 2     
Guadalupe River
 
LOE ID: 274848
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for nickel is the probable effect concentration (PEC) of 48.6 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141999, Nickel
Region 2     
Guadalupe River
 
LOE ID: 91893
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Nickel.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for nickel is 48.6 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142001
Region 2     
Guadalupe River
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285738
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285904
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285722
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285849
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 286668
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 9 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected between the dates of 2014-06-25 and 2020-07-17
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285737
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285723
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 9 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected between the dates of 2014-06-25 and 2020-07-17
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285739
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 286521
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285608
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 286231
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285655
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285907
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 285654
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as cold water habitat shall be of a 7.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 286575
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142001, Oxygen, Dissolved
Region 2     
Guadalupe River
 
LOE ID: 286435
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen objectives for waters designated as warm water habitat shall be of a 5.0 mg/l minimum. (Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives.)
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
148824
Region 2     
Guadalupe River
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
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 148824, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 2     
Guadalupe River
 
LOE ID: 275218
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for total PAHs is the probable effect concentration (PEC) of 22800 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 148824, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 2     
Guadalupe River
 
LOE ID: 91822
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for PAHs (Polycyclic Aromatic Hydrocarbons).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for PAH, Total is 22,800 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 148824, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 2     
Guadalupe River
 
LOE ID: 275068
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for PAHs (Polycyclic Aromatic Hydrocarbons) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for total PAHs is the probable effect concentration (PEC) of 22800 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 148824, PAHs (Polycyclic Aromatic Hydrocarbons)
Region 2     
Guadalupe River
 
LOE ID: 91821
 
Pollutant: PAHs (Polycyclic Aromatic Hydrocarbons)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for PAHs (Polycyclic Aromatic Hydrocarbons).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for PAH, Total is 22,800 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142004
Region 2     
Guadalupe River
 
Pollutant: PCBs (Polychlorinated biphenyls)
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142004, PCBs (Polychlorinated biphenyls)
Region 2     
Guadalupe River
 
LOE ID: 275389
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for total PCBs is the probable effect concentration (PEC) of 676 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2017-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142004, PCBs (Polychlorinated biphenyls)
Region 2     
Guadalupe River
 
LOE ID: 90584
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 1 sample collected for Total PCBs exceeded the evaluation guideline.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses (Water Quality Control Plan for the San Francisco Bay Region).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity) for total PCB is 676 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected on 6/17/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142004, PCBs (Polychlorinated biphenyls)
Region 2     
Guadalupe River
 
LOE ID: 275449
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for total PCBs is the probable effect concentration (PEC) of 676 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2017-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142027
Region 2     
Guadalupe River
 
Pollutant: Permethrin
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142027, Permethrin
Region 2     
Guadalupe River
 
LOE ID: 286543
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142027, Permethrin
Region 2     
Guadalupe River
 
LOE ID: 286471
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142027, Permethrin
Region 2     
Guadalupe River
 
LOE ID: 275476
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142027, Permethrin
Region 2     
Guadalupe River
 
LOE ID: 275273
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142027, Permethrin
Region 2     
Guadalupe River
 
LOE ID: 91824
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142027, Permethrin
Region 2     
Guadalupe River
 
LOE ID: 91823
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, Total.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142003
Region 2     
Guadalupe River
 
Pollutant: Phenanthrene
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142003, Phenanthrene
Region 2     
Guadalupe River
 
LOE ID: 275305
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for phenanthrene is the probable effect concentration (PEC) of 1170 ug/kg dry weight (MacDonald et al.).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142003, Phenanthrene
Region 2     
Guadalupe River
 
LOE ID: 91825
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Phenanthrene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Phenanthrene is 1170 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142003, Phenanthrene
Region 2     
Guadalupe River
 
LOE ID: 91826
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Phenanthrene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Phenanthrene is 1170 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142003, Phenanthrene
Region 2     
Guadalupe River
 
LOE ID: 275345
 
Pollutant: Phenanthrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Phenanthrene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for phenanthrene is the probable effect concentration (PEC) of 1170 ug/kg dry weight (MacDonald et al.).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142005
Region 2     
Guadalupe River
 
Pollutant: Pyrene
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 142005, Pyrene
Region 2     
Guadalupe River
 
LOE ID: 275565
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for pyrene is the probable effect concentration (PEC) of 1520 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142005, Pyrene
Region 2     
Guadalupe River
 
LOE ID: 91827
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Pyrene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Pyrene is 1520 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142005, Pyrene
Region 2     
Guadalupe River
 
LOE ID: 91828
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Pyrene.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effects level (predictive of sediment toxicity for sediment-dwelling organisms) for Pyrene is 1520 ug/Kg dry weight (Macdonald et al. 2000)
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142005, Pyrene
Region 2     
Guadalupe River
 
LOE ID: 275619
 
Pollutant: Pyrene
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 9 samples exceeded the evaluation guideline for Pyrene .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for pyrene is the probable effect concentration (PEC) of 1520 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142006
Region 2     
Guadalupe River
 
Pollutant: Temperature, water
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 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298608
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298595
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 10
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and results are as follows: 3 of 10 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected between the dates of 2013-06-26 and 2020-07-17
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298667
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298659
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298559
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298718
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 288884
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 288829
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 288921
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 289053
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 289037
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 288799
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 288899
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected between the dates of 2013-06-26 and 2020-07-17
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 288816
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: “- The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. - The temperature of any cold or warm freshwater habitat shall not be increased by more than 5°F (2.8°C) above natural receiving water temperature.”
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Per Effects of Temperature, Dissolved Oxygen/Total Dissolved Gas, Ammonia, and pH on Salmonids (Carter 2008, Moyle 1976, and USEPA 1977), the lethal temperature evaluation guideline for both the steelhead adult migration and holding and the steelhead juvenile growth and rearing life stages is 24°C.
Guideline Reference: Temperature criteria for freshwater fish: protocol and procedures. Ecological Research Series. EPA-600/3-77-061 (NTIS PB270032). Prepared by W.A. Brungs and B.R. Jones. U.S. Environmental Protection Agency, Washington, D.C
Guideline Reference: Inland Fishes of California
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: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298756
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142006, Temperature, water
Region 2     
Guadalupe River
 
LOE ID: 298704
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for surface waters are specified in the San Francisco Bay Regional Water Quality Control Plan. The following temperature objectives apply to surface waters: The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of any cold or warm freshwater habitat shall not be increased by more than 5 degrees F (2.8 degrees C) above natural receiving water temperature.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Scientific literature reviewed by the Washington Department of Ecology and U.S. EPA indicates that stream temperatures higher than 21C are associated with avoidance behavior and migration blockages in steelhead trout.
Guideline Reference: EPA Region 10 Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards. EPA 910-B-03-002. Region 10 Office of Water, Seattle, WA
Guideline Reference: U.S. Environmental Protection Agency (USEPA). 2001. Issue Paper 1: Salmonid Behavior and Water Temperature Prepared as Part of EPA Region 10 Temperature Water Quality Criteria Guidance Development Project. Region 10, Seattle, WA. EPA-910-D-01-001 May 2001.
Guideline Reference: Washington State Department of Ecology (WDOE). 2002. Evaluating Standards for Protecting Aquatic Life in Washington’s Surface Water Quality Standards: Temperature Criteria. Draft Discussion Paper and Literature Summary. Publication Number 00-10-070.
Guideline Reference: Beschta RL, Bilby RE, Brown GW, Holtby LB, Hofstra TD. 1987. Stream temperature and aquatic habitat: Fisheries and forestry interactions. In: Salo EO, Cundy TW, eds. Streamside management: forestry and fishery interactions. College of Forest Resources, University of Washington, Seattle. Contribution No. 57. Proceedings of a Symposium held at University of Washington, February 12-14, 1986, pp. 191-231.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
142017
Region 2     
Guadalupe River
 
Pollutant: Triclopyr
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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142017, Triclopyr
Region 2     
Guadalupe River
 
LOE ID: 289151
 
Pollutant: Triclopyr
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Triclopyr.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142017, Triclopyr
Region 2     
Guadalupe River
 
LOE ID: 289169
 
Pollutant: Triclopyr
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Triclopyr.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for triclopyr is the USEPA Aquatic Life Benchmark of 26 ug/L for a fish (chronic) for Triclopyr Butoxyethyl Ester (BEE).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2014-07-07 and 2014-08-04
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
142008
Region 2     
Guadalupe River
 
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 142008, Turbidity
Region 2     
Guadalupe River
 
LOE ID: 302692
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009). The application of this evaluation guideline was restricted to the dry season (May to October) because runoff and resuspension of fine substrate during storm events may naturally elevate turbidity compared to baseflow conditions. The magnitude and duration of these increases will vary depending on the watershed’s geology and land use and may not represent a chronic turbidity problem. Turbidity is naturally higher in tidal river systems, so sample locations with salinity regimes (i.e., Freshwater or Marine) designated as “Marine” were excluded from this analysis.
Guideline Reference: The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142008, Turbidity
Region 2     
Guadalupe River
 
LOE ID: 289369
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Turbidity.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTUs or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food. The application of this evaluation guideline was restricted to the dry season (May to October) because Coho and steelhead early life stages are present during the dry season and feeding becomes infrequent during the winter months (Moyle 2002). Additionally, runoff and resuspension of fine substrate during storm events may naturally elevate turbidity compared to baseflow conditions. The magnitude and duration of these increases will vary depending on the watershed’s geology and land use and may not represent a chronic turbidity problem. Turbidity is naturally higher in tidal river systems, so sample locations with salinity regimes (i.e., Freshwater or Marine) designated as “Marine” were excluded from this analysis.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142009
Region 2     
Guadalupe River
 
Pollutant: Zinc
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 142009, Zinc
Region 2     
Guadalupe River
 
LOE ID: 91833
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142009, Zinc
Region 2     
Guadalupe River
 
LOE ID: 276290
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for zinc is the probable effect concentration (PEC) of 459 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142009, Zinc
Region 2     
Guadalupe River
 
LOE ID: 276490
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for zinc is the probable effect concentration (PEC) of 459 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2018-06-27
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142009, Zinc
Region 2     
Guadalupe River
 
LOE ID: 91832
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Zinc.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for zinc is 459 mg/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
142002
Region 2     
Guadalupe River
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: 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 this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287590
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01114 (Almaden Expressway at Koch).
Temporal Representation: The samples were collected between the dates of 2016-05-03 and 2016-05-03
Environmental Conditions:
QAPP Information: EOA, Inc.. 2016. Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287398
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00259 (Guadalupe River at the San Jose Airport-205R00259).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287148
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00346 (Guadalupe River - 300 m upstream Branham Ln-205R00346).
Temporal Representation: The samples were collected between the dates of 2012-06-14 and 2012-06-14
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287589
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Perennial Stream Surveys data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205PS0109 (Guadalupe River below Curtner Ave.).
Temporal Representation: The samples were collected between the dates of 2011-06-21 and 2011-06-21
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287610
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 9 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected between the dates of 2014-06-25 and 2020-07-17
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287634
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2015 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R02051 (Guadalupe River Between Coleman and Taylor).
Temporal Representation: The samples were collected between the dates of 2015-05-19 and 2015-05-19
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287280
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2014 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R01027 (Guadalupe River at W. Rosemary St).
Temporal Representation: The samples were collected between the dates of 2014-05-05 and 2014-05-05
Environmental Conditions:
QAPP Information: EOA, Inc.. 2014. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 142002, pH
Region 2     
Guadalupe River
 
LOE ID: 287279
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.9 pH states: The pH shall not be depressed below 6.5 nor raised above 8.5. This encompasses the pH range usually found in waters within the basin. Controllable water quality factors shall not cause changes greater than 0.5 units in normal ambient pH levels.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205R00771 (Guadalupe River 150 m downstream Coleman Ave-205R00771).
Temporal Representation: The samples were collected between the dates of 2013-06-06 and 2013-06-06
Environmental Conditions:
QAPP Information: EOA, Inc.. 2012. Creek Status Monitoring Program Quality Assurance Project Plan.
QAPP Information Reference(s): Creek Status Monitoring Program Quality Assurance Project Plan
 
 
DECISION ID
141983
Region 2     
Guadalupe River
 
Pollutant: Chlordane
Final Listing Decision: 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
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Six lines of evidence are available in the administrative record to assess this pollutant. Six of the seven samples exceed the COLD evaluation guideline. Five of eleven samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is SUFFICIENT justification FOR 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. Six of the seven samples exceed the evaluation guideline and this sample size is SUFFICIENT to determine beneficial use support, with the power and confidence of the Listing Policy. There is associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 141983, Chlordane
Region 2     
Guadalupe River
 
LOE ID: 270945
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlordane is the probable effect concentration (PEC) of 17.6 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141983, Chlordane
Region 2     
Guadalupe River
 
LOE ID: 91831
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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. Region 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. . For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 205GUA020.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 141983, Chlordane
Region 2     
Guadalupe River
 
LOE ID: 90712
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 1 of 1 samples collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Waters shall not contain substances in concentrations that result in the deposition of material that causes nuisance or adversely affects beneficial uses. (Water Quality Control Plan for the San Francisco Bay Basin).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: The samples were collected on 6/17/2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 141983, Chlordane
Region 2     
Guadalupe River
 
LOE ID: 269082
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141983, Chlordane
Region 2     
Guadalupe River
 
LOE ID: 270828
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for chlordane is the probable effect concentration (PEC) of 17.6 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 141983, Chlordane
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142015
Region 2     
Guadalupe River
 
Pollutant: Bifenthrin
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: Other Urban Runoff | Surface Runoff
TMDL Name: San Francisco Bay Urban Creeks Diazinon
TMDL Project Code: 9
Date TMDL Approved by USEPA: 05/21/2007
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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Nine lines of evidence are available in the administrative record to assess this pollutant. Two of the ten samples exceed the evaluation guideline. Five of eleven samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is SUFFICIENT justification FOR 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. Two of the ten samples exceed the evaluation guideline and this sample size is SUFFICIENT to determine beneficial use support, with the power and confidence of the Listing Policy. There is an associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 91831
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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. Region 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. . For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 205GUA020.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 91778
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Bifenthrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 91777
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Guadalupe River to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Bifenthrin.
Data Reference: Statewide Stream Pollution Trends Study 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: San Francisco Bay Basin Water Quality Control Plan 2007: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Guadalupe River was collected at 1 monitoring site [ Guadalupe Creek @ USGS Gaging Station 11169025 station (205GUA020)]
Temporal Representation: Data was collected on a single day 6/17/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002), however there may have been overlap in QA with SWAMP QAPP (2008).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 270221
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 2 of the 9 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 280646
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Bifenthrin. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
 
Spatial Representation: The samples were collected at 1 monitoring site (Santa Clara 27).
Temporal Representation: Data for this waterbody was collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 270323
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 2 of the 9 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 269082
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142015, Bifenthrin
Region 2     
Guadalupe River
 
LOE ID: 280601
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and the results are as follows: 1 of the 1 samples exceeded the water quality threshold for Bifenthrin. Although a total of 4 samples were collected, 3 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The chronic criterion for bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
 
Spatial Representation: The samples were collected at 1 monitoring site (Santa Clara 27).
Temporal Representation: Data for this waterbody was collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
 
DECISION ID
142010
Region 2     
Guadalupe River
 
Pollutant: Pyrethroids
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Other Urban Runoff | Surface Runoff
TMDL Name: San Francisco Bay Urban Creeks Diazinon
TMDL Project Code: 9
Date TMDL Approved by USEPA: 05/21/2007
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 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Nine lines of evidence are available in the administrative record to assess this pollutant. Five of the nine samples exceed the evaluation guideline. Five of eleven samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is SUFFICIENT justification FOR 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. Five of the nine samples exceed the evaluation guideline and this sample size is SUFFICIENT to determine beneficial use support, with the power and confidence of the Listing Policy. There is an associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 269082
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 91831
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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. Region 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. . For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 205GUA020.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 275991
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 9 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 287683
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 287647
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Pyrethroids. Although a total of 4 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: Data for this waterbody were collected over the date range 2014-07-07 to 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 287764
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2015-12-10 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 287761
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Surface Water Monitoring Project data for Guadalupe River to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Pyrethroids.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the San Francisco Bay Basin: Controllable water quality factors shall not cause a detrimental increase in concentrations of toxic substances found in bottom sediments or aquatic life. Effects on aquatic organisms, wildlife, and human health will be considered.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The summed ratios of the pyrethroid pesticides bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, permethrin and their respective chronic concentration goals are not to exceed 1. If the freely dissolved concentrations of these pesticides were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Amendment to the Water Quality Control Plan for the Sacramento River and San Joaquin River Basins for the Control of Pyrethroid Pesticide Discharges
 
Spatial Representation: The samples were collected at 1 monitoring site: Santa Clara 27 (Guadalupe River at Trimble Rd).
Temporal Representation: The samples were collected between the dates of 2015-12-10 and 2015-12-10
Environmental Conditions:
QAPP Information: USEPA DPR. 2019. STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020).
QAPP Information Reference(s): STUDY 299: Pesticide Monitoring in Urban Areas of Northern California (FY 2019/2020)
 
Line of Evidence (LOE) for Decision ID 142010, Pyrethroids
Region 2     
Guadalupe River
 
LOE ID: 275744
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 9 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
142007
Region 2     
Guadalupe River
 
Pollutant: Toxicity
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: Other Urban Runoff | Surface Runoff
TMDL Name: San Francisco Bay Urban Creeks Diazinon
TMDL Project Code: 9
Date TMDL Approved by USEPA: 05/21/2007
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 3.6 of the Listing Policy. Under section 3.6 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Five of eleven samples exceed the evaluation guideline for sediment toxicity.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of eleven samples exceed the guideline and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. Additionally, there are corresponding exceedances for pyrethroids and bifenthrin.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 275744
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 9 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 91831
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample did not exhibit significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Stream Pollution Trends Study 2008
 
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. Region 2 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. . For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 205GUA020.
Temporal Representation: The sample was collected in June 2008.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 269082
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 269083
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 10 samples collected by SWAMP Stream Pollution Trends for Guadalupe River exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv), Chironomus dilutus for Growth (wt/surv indiv), Chironomus dilutus for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-07-08, Hyalella azteca for Growth (wt/surv indiv) on 2012-07-05, Hyalella azteca for Growth (wt/surv indiv) on 2013-06-26, Hyalella azteca for Survival on 2014-06-25, Hyalella azteca for Growth (wt/surv indiv) on 2019-07-02.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms. Detrimental responses include, but are not limited to, decreased growth rate and decreased reproductive success of resident or indicator species. There shall be no acute toxicity in ambient waters. Acute toxicity is defined as a median of less than 90 percent survival, or less than 70 percent survival, 10 percent of the time, of test organisms in a 96-hour static or continuous flow test. There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community. Attainment of this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, or toxicity tests (including those described in Chapter 4), or other methods selected by the Water Board. The Water Board will also consider other relevant information and numeric criteria and guidelines for toxic substances developed by other agencies as appropriate.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 205GUA020 ( Guadalupe Creek @ USGS Gaging Station 11169025 ).
Temporal Representation: The samples were collected between the dates of 2011-07-08 and 2020-07-17.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 270323
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 2 of the 9 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 270221
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 2 of the 9 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 142007, Toxicity
Region 2     
Guadalupe River
 
LOE ID: 275991
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 9
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Guadalupe River to determine beneficial use support and the results are as follows: 5 of the 9 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Section 3.3.18 of the San Francisco Bay Region's Basin Plan contains the narrative toxicity objective stating that all waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) San Francisco Bay Basin (Region 2)
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 205GUA020 (Guadalupe Creek @ USGS Gaging Station 11169025).
Temporal Representation: Data for this waterbody were collected over the date range 2011-07-08 to 2019-07-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
87599
Region 2     
Guadalupe River
 
Pollutant: Trash
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with action other than TMDL)(2016)
Revision Status Original
Sources: A Source Unknown
Expected Attainment Date: 2029
Implementation Action Other than TMDL: This trash listing will be addressed by implementing the trash control provisions of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California through the NPDES MS4 permit applicable to this waterbody.
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.11 of the Listing Policy. Under section 3.11, listing may be proposed based on the situation-specific weight of evidence. Two lines of evidence are available in the administrative record to assess this pollutant. The first line of evidence concerns the non-contact recreation beneficial use, and the second line of evidence concerns the wildlife habit beneficial use. Both lines of evidence make use of data from field visits/trash surveys conducted according to the Urban Rapid Trash Assessment (URTA) methodology developed by the Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP) as well as inspection of photographic evidence by Regional Water Board staff trained to conduct the Rapid Trash Assessment (RTA) methodology. The staff inspected these photos and applied the RTA methodology to develop Category 1 (Level of Trash) and Category 3 (Threat to Aquatic Life) scores for each photograph. Based on the readily available photographic and trash assessment data for this waterbody, the weight of evidence indicates that there is sufficient justification available in favor of placing this water segment-pollutant combination to the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. Data have been evaluated that supports this decision. 2. The Urban Rapid Trash Assessment methodology results showed that this waterbody had level of trash parameter scores in the poor category (indicating impairment of non-contact water recreational beneficial uses) at three locations and on three different dates. This waterbody also had transportable, Persistent, Buoyant Litter parameter scores in the marginal urban and poor category (indicating threat to Wildlife Habitat beneficial uses) at four locations and on four different dates. 3. Photographic evidence has been evaluated that supports this decision. 4. Applying the Rapid Trash Assessment methodology to the photographic evidence suggests that this waterbody had level of trash parameter scores in the poor category (indicating impairment of non-contact water recreational beneficial uses) at more than five locations on six different dates. This waterbody also had threat to aquatic life parameter scores in the poor category (indicating threat to Wildlife Habitat beneficial uses) at more than six different locations on seven different dates. 5. This waterbody is considered impaired by trash because there were exceedances of the evaluation guidelines (poor condition category for the trash assessment metrics) in more than one location or on more than one date. 6. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 7. The data used satisfy the data quantity requirements of section 6.1 of the Policy.
8. This trash listing will be addressed by implementing the trash control provisions of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California through the NPDES MS4 permit applicable to this waterbody.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
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 87599, Trash
Region 2     
Guadalupe River
 
LOE ID: 5479
 
Pollutant: Trash
LOE Subgroup: Pollutant-Nuisance
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Wildlife Habitat
 
Number of Samples: 8
Number of Exceedances: 8
 
Data and Information Type: Occurrence of conditions judged to cause impairment
Data Used to Assess Water Quality: Data available consist of photographic evidence of trash and interpretation of these photos by an experienced trash assessment specialist. Each photograph was analyzed to establish the RTA score for the level of trash and threat to aquatic life parameters, which relate to impairment of REC2 and WILD, respectively. Only those photos clear enough to establish these RTA scores were relied on for the listing determination. These results are available for the following Guadalupe River locations:
Multiple locations on 2/1/2004, 2/18/2005, and 2/2/2006
San Jose Airport on 2/18/2005
Alma Ave. on 2/24/2007
Malone Ave. on 2/24/2007
Between Tasman and Trimble on 2/19/2007
75 yards upstream of I880 on 1/22/2007
At the Montague Expressway on 5/8/2006

This waterbody had threat to aquatic life parameter scores in the poor category (indicating threat to Wildlife Habitat beneficial uses) at more than six different locations on seven different dates.
Data Reference: Report from Roger James and Larry Kolb containing Trash Photos submitted for consideration in 2008 303(d) listing process
  Assessment by Matt Cover of Trash Photos (submitted to Region 2 in response to 2008 Data Solicitation)
  Archive of Trash Photos for Guadalupe River submitted for 2008 303(d) list consideration
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan prohibits discharge of Rubbish, refuse, bark, sawdust, or other solid wastes into surface waters or at any place where they would contact or where they would be eventually transported to surface waters, including flood plain areas.

The Basin Plan has a narrative objective for floating material, Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses.

The Basin Plan has a narrative objective for settleable material, Waters shall not contain substances in concentrations that result in the deposition of material that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: If the RTA Parameter 3 (Threat to Aquatic Life) is in the poor condition category (scores 0-5), then WILD is not supported. This level of trash is a large amount (>50 pieces) of transportable, persistent, buoyant litter that is detrimental to aquatic life. The RTA defines poor condition for this parameter as follows, large amount (>50 pieces) of transportable, persistent, buoyant litter such as: hard or soft plastics, balloons, Styrofoam, cigarette butts; toxic items such as batteries, lighters, or spray cans; large clumps of yard waste or dumped leaf litter; or large amount (>50 pieces) of settleable glass or metal.

Regional Water Board staff trained in the RTA inspected the available photographic evidence and applied the assessment method to determine the Threat to Aquatic Life score.
Guideline Reference: A Rapid Trash Assessment Method Applied to Waters of the San Francisco Bay Region:Trash Measurement in Streams
 
Spatial Representation: Photographic evidence was analyzed using the RTA methodology for this waterbody for more than seven different locations spanning dates from 2004 through 2007.
Temporal Representation: Photographic evidence was collected for this waterbody on seven separate dates from 2004 through 2007.
Environmental Conditions:
QAPP Information: Assessments of the photographic evidence using the RTA were performed by Regional Water Board staff person who was a co-author of the Rapid Trash Assessment methodology.

Assessments based on photographic evidence were only conducted when sufficient reach-scale and close-up photos were available for a site on a specific date. Photos used for the evaluation needed to be numerous enough and clear enough to document the level of trash at the site in a similar way as the assessor would experience during an actual site visit in the field. For example, at a minimum, one reach-scale photograph (showing at least a 100 linear foot section of the waterbody) and two close-up photographs (of representative trash deposits) were required.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 87599, Trash
Region 2     
Guadalupe River
 
LOE ID: 5480
 
Pollutant: Trash
LOE Subgroup: Pollutant-Nuisance
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 7
 
Data and Information Type: Occurrence of conditions judged to cause impairment
Data Used to Assess Water Quality: Data available consist of photographic evidence of trash and interpretation of these photos by an experienced trash assessment specialist. Each photograph was analyzed to establish the RTA score for the level of trash and threat to aquatic life parameters, which relate to impairment of REC2 and WILD, respectively. Only those photos clear enough to establish these RTA scores were relied on for the listing determination. These results are available for the following Guadalupe River locations:
Multiple locations on 2/1/2004, 2/18/2005, and 2/2/2006
San Jose Airport on 2/18/2005
Alma Ave. on 2/24/2007
Malone Ave. on 2/24/2007
Between Tasman and Trimble on 2/19/2007
75 yards upstream of I880 on 1/22/2007
At the Montague Expressway on 5/8/2006

This waterbody had level of trash parameter scores in the poor category (indicating impairment of non-contact water recreational beneficial uses) at five locations on six different dates.
Data Reference: Report from Roger James and Larry Kolb containing Trash Photos submitted for consideration in 2008 303(d) listing process
  Assessment by Matt Cover of Trash Photos (submitted to Region 2 in response to 2008 Data Solicitation)
  Archive of Trash Photos for Guadalupe River submitted for 2008 303(d) list consideration
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan prohibits discharge of Rubbish, refuse, bark, sawdust, or other solid wastes into surface waters or at any place where they would contact or where they would be eventually transported to surface waters, including flood plain areas.

The Basin Plan has a narrative objective for floating material, Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses.

The Basin Plan has a narrative objective for settleable material, Waters shall not contain substances in concentrations that result in the deposition of material that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: If the Rapid Trash Assessment (RTA) Parameter 1 (Level of Trash) is in the poor condition category (scores 0-5), REC2 is not supported. This level of trash distracts the eye on first glance, making the site unsuitable for recreation. The RTA defines poor condition for this parameter as follows, trash distracts the eye on first glance. Stream, bank surfaces, and immediate riparian zone contain substantial levels of litter and debris (>100 pieces). Evidence of site being used frequently by people: many cans, bottles, and food wrappers, blankets, clothing.

Regional Water Board staff trained in the RTA inspected the available photographic evidence and applied the assessment method to determine the Level of Trash score.
Guideline Reference: A Rapid Trash Assessment Method Applied to Waters of the San Francisco Bay Region:Trash Measurement in Streams
 
Spatial Representation: Photographic evidence was analyzed using the RTA methodology for this waterbody for more than seven different locations spanning dates from 2004 through 2007.
Temporal Representation: Photographic evidence was collected for this waterbody on seven separate dates from 2004 through 2007.
Environmental Conditions:
QAPP Information: Assessments of the photographic evidence using the RTA were performed by Regional Water Board staff person who was a co-author of the Rapid Trash Assessment methodology.

Assessments based on photographic evidence were only conducted when sufficient reach-scale and close-up photos were available for a site on a specific date. Photos used for the evaluation needed to be numerous enough and clear enough to document the level of trash at the site in a similar way as the assessor would experience during an actual site visit in the field. For example, at a minimum, one reach-scale photograph (showing at least a 100 linear foot section of the waterbody) and two close-up photographs (of representative trash deposits) were required.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 87599, Trash
Region 2     
Guadalupe River
 
LOE ID: 5478
 
Pollutant: Trash
LOE Subgroup: Pollutant-Nuisance
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 5
 
Data and Information Type: Occurrence of conditions judged to cause impairment
Data Used to Assess Water Quality: Data results were obtained through application of the Urban Rapid Trash Assessment (URTA) methodology, developed by the Santa Clara Valley Urban Runoff Pollution Prevention Program. The URTA is a modification of the Rapid Trash Assessment (RTA) developed by the Surface Water Ambient Monitoring Program (SWAMP). The URTA method documents the total number and characteristics of pieces of trash per one hundred feet of stream or shoreline. The trash assessment protocol involves picking up and tallying all of the trash items found within the defined boundaries of a site. The tally results for level of trash (relating to REC2) and transportable, persistent, buoyant litter (relating to WILD) assessment parameters were considered for the listing determination. These results are available for field visits/trash surveys conducted in September 2004, an unknown date in 2005, and November 2006 according to the Urban Rapid Trash Assessment (URTA) methodology.

This waterbody had level of trash parameter scores in the poor category (indicating impairment of non-contact water recreational beneficial uses) at three locations and on three different dates.
Data Reference: Memo: Development of Urban Rapid Trash Assessment Protocol. March 13, 2006
  Spreadsheet of Urban Rapid Trash Assessment (URTA) data collected by the Santa Clara Valley Urban Runoff Pollution Prevention Program, 2004-2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan prohibits discharge of Rubbish, refuse, bark, sawdust, or other solid wastes into surface waters or at any place where they would contact or where they would be eventually transported to surface waters, including flood plain areas.

The Basin Plan has a narrative objective for floating material, Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses.

The Basin Plan has a narrative objective for settleable material, Waters shall not contain substances in concentrations that result in the deposition of material that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: If the Urban Rapid Trash Assessment (URTA) Parameter 1 (Level of Trash) is in the poor condition category (scores 0-5), REC2 is not supported. The URTA defines poor condition for this parameter as a level of trash that distracts the eye on first glance. Stream, bank surfaces, and immediate riparian zone contain substantial levels of litter and debris. Evidence of site being used frequently by people: many cans, bottles, and food wrappers, blankets, clothing.
Guideline Reference: Memo: Development of Urban Rapid Trash Assessment Protocol. March 13, 2006
 
Spatial Representation: URTA data were collected for this waterbody in five locations in 2004 through 2006.
Temporal Representation: URTA data was collected for this waterbody on five separate dates from September 2004 through November 2006.
Environmental Conditions:
QAPP Information: Data were collected by trained staff in accordance with URTA methodology developed by SCVURPPP and are deemed reliable and of sufficient quality on which to base listing determinations.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 87599, Trash
Region 2     
Guadalupe River
 
LOE ID: 5477
 
Pollutant: Trash
LOE Subgroup: Pollutant-Nuisance
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Wildlife Habitat
 
Number of Samples: 8
Number of Exceedances: 7
 
Data and Information Type: Occurrence of conditions judged to cause impairment
Data Used to Assess Water Quality: Data results were obtained through application of the Urban Rapid Trash Assessment (URTA) methodology, developed by the Santa Clara Valley Urban Runoff Pollution Prevention Program. The URTA is a modification of the Rapid Trash Assessment (RTA) developed by the Surface Water Ambient Monitoring Program (SWAMP). The URTA method documents the total number and characteristics of pieces of trash per one hundred feet of stream or shoreline. The trash assessment protocol involves picking up and tallying all of the trash items found within the defined boundaries of a site. The tally results for level of trash (relating to REC2) and transportable, persistent, buoyant litter (relating to WILD) assessment parameters were considered for the listing determination. These results are available for field visits/trash surveys conducted in September 2004, an unknown date in 2005, and November 2006 according to the Urban Rapid Trash Assessment (URTA) methodology. This waterbody had transportable, Persistent, Buoyant Litter parameter scores in the marginal urban and poor category (indicating threat to Wildlife Habitat beneficial uses) at four locations and on four different dates.
Data Reference: Memo: Development of Urban Rapid Trash Assessment Protocol. March 13, 2006
  Spreadsheet of Urban Rapid Trash Assessment (URTA) data collected by the Santa Clara Valley Urban Runoff Pollution Prevention Program, 2004-2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan prohibits discharge of Rubbish, refuse, bark, sawdust, or other solid wastes into surface waters or at any place where they would contact or where they would be eventually transported to surface waters, including flood plain areas.

The Basin Plan has a narrative objective for floating material, Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses.

The Basin Plan has a narrative objective for settleable material, Waters shall not contain substances in concentrations that result in the deposition of material that cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - San Francisco Bay Region (Region 2)
 
Evaluation Guideline: If the URTA Parameter 3 (Transportable, Persistent, Buoyant Litter) is in the marginal urban or poor condition category (scores 0-10), then WILD is not supported. The URTA defines marginal urban or poor condition for this parameter as follows. this level of trash is a medium prevalence (76-200 pieces) or large amount (>200 pieces) of transportable, persistent, buoyant litter such as: hard or soft plastics, styrofoam, balloons, cigarette butts. These types of items are all detrimental to aquatic life.
Guideline Reference: Memo: Development of Urban Rapid Trash Assessment Protocol. March 13, 2006
 
Spatial Representation: URTA data were collected for this waterbody in five locations in 2004 through 2006.
Temporal Representation: URTA data were collected for this waterbody on five separate dates from September 2004 through November 2006.
Environmental Conditions:
QAPP Information: Data were collected by trained staff in accordance with URTA methodology developed by SCVURPPP and are deemed reliable and of sufficient quality on which to base listing determinations.
QAPP Information Reference(s):