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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name: Calabazas Creek (Santa Clara County)
Water Body ID: CAR2055004020120423095155
Water Body Type: River & Stream
 
DECISION ID
143327
Region 2     
Calabazas Creek (Santa Clara County)
 
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:
 
 
Line of Evidence (LOE) for Decision ID 143327, Alkalinity as CaCO3
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 276817
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143327, Alkalinity as CaCO3
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 276818
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143327, Alkalinity as CaCO3
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 276836
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143327, Alkalinity as CaCO3
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 276819
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143327, Alkalinity as CaCO3
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 276834
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143327, Alkalinity as CaCO3
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 276835
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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
150866
Region 2     
Calabazas Creek (Santa Clara County)
 
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279845
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279651
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279489
 
Pollutant: Ammonia (Unionized)
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 WY2017 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279215
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279234
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279404
 
Pollutant: Ammonia (Unionized)
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 WY2017 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279948
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277913
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277543
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277911
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278342
 
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: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278047
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278204
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278340
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278338
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277893
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277711
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278339
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277912
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277727
 
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: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277892
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 278341
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 277746
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279467
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279060
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279236
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279214
 
Pollutant: Ammonia (Unionized)
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 BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 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: 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: Data for this waterbody were collected over the date range 2013-06-04 to 2013-06-04
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279406
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279107
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 150866, Ammonia
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 279846
 
Pollutant: Ammonia (Unionized)
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 BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Ammonia as N, Unionized. Although a total of 1 samples were collected, 1 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: 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: Data for this waterbody were collected over the date range 2013-06-04 to 2013-06-04
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
154575
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Benthic Community Effects
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects.

Section 3.9 of the Listing Policy requires degradation of biological populations in a segment when compared to reference and the segment is associated with pollutant concentrations affecting aquatic life beneficial uses. While the waterbody is listed for diazinon, diazinon is not viewed as an associated pollutant concentration because information indicates diazinon likely no longer persists in the waterbody or is otherwise significantly diminished. First, the diazinon data were collected prior to a 2004 ban on the residential use of diazinon. Second, the waterbody drains a watershed primarily composed of residential and urban land uses. Agricultural land use makes up 0.7% of land use within 1 km of the waterbody, 0.5% within 5 km of the waterbody, and 0.3% within the watershed. Third, diazinon is not persistent in the environment and concentrations in waterbodies from discharges that occurred more than 1 year ago may be minimal to non-existent. The half life of diazinon ranges up to 138 days in water and 103 days in soil; 10 half-lives in water is 280 days. These data indicate that the waterbody is likely unimpaired for Benthic Community Effects and therefore no other pollutant LOEs need be associated with this decision at this time.

Seven line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/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. These data indicate that the waterbody is likely unimpaired for Benthic Community Effects and therefore no other pollutant LOEs need be associated with this decision at this time.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Seven of seven benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. This water body is not exceeding the water quality threshold for the protection of the COLD beneficial use. The available information indicates that the waterbody/pollutant combination should not be placed on the 303(d) List of impaired waters at this time.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306560
 
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 205R04266 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.511151919 to 0.511151919.
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 205R04266.
Temporal Representation: Samples were collected from 5/2/2018 to 5/2/2018.
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 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306559
 
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 205R03875 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.459479623 to 0.459479623.
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 205R03875.
Temporal Representation: Samples were collected from 5/2/2018 to 5/2/2018.
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 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306548
 
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 205R02538 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.572511 to 0.572511.
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 205R02538.
Temporal Representation: Samples were collected from 5/18/2016 to 5/18/2016.
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 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306549
 
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 205R03443 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.446960757 to 0.446960757.
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 205R03443.
Temporal Representation: Samples were collected from 6/1/2017 to 6/1/2017.
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 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306537
 
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 205R00547 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.461038 to 0.461038.
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 205R00547.
Temporal Representation: Samples were collected from 6/4/2013 to 6/4/2013.
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 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306547
 
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 205R00627 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.509505 to 0.509505.
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 205R00627.
Temporal Representation: Samples were collected from 6/4/2013 to 6/4/2013.
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 154575, Benthic Community Effects
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 306536
 
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 205R00099 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.608819 to 0.608819.
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 205R00099.
Temporal Representation: Samples were collected from 5/17/2012 to 5/17/2012.
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
 
 
DECISION ID
143325
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Bifenthrin
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:
 
 
Line of Evidence (LOE) for Decision ID 143325, Bifenthrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 280580
 
Pollutant: Bifenthrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143325, Bifenthrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 280648
 
Pollutant: Bifenthrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143315
Region 2     
Calabazas Creek (Santa Clara County)
 
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:
 
 
Line of Evidence (LOE) for Decision ID 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281634
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281371
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281426
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281445
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281086
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281464
 
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 WY2017 data for Calabazas Creek (Santa Clara County) 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 280840
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 280797
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281611
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281446
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281087
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281167
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281089
 
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 WY2017 data for Calabazas Creek (Santa Clara County) 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281090
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281278
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 280689
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281392
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281088
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 280692
 
Pollutant: Chloride
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Calabazas Creek (Santa Clara County) 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, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for chloride is 355.0 mg/l.
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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281070
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143315, Chloride
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281555
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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
143316
Region 2     
Calabazas Creek (Santa Clara County)
 
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282373
 
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 WY2017 data for Calabazas Creek (Santa Clara County) 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282463
 
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 WY2017 data for Calabazas Creek (Santa Clara County) 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282391
 
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 WY2013 data for Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282108
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282006
 
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 WY2013 data for Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282659
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 281964
 
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 WY2013 data for Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282145
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282207
 
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 WY2013 data for Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143316, Chlorine
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 282519
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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
143317
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Copper
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:
 
 
Line of Evidence (LOE) for Decision ID 143317, Copper
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283152
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold 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: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-05-21
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 143317, Copper
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283345
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
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 BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold 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: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-05-21
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 143317, Copper
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283391
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Agricultural Supply
 
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 BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold 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: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The copper limit for irrigation and livestock watering supply is 5.0 mg/L and 0.5 mg/l, respectively.
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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-05-21
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 143317, Copper
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283325
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
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 BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold 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: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Francisco Bay Basin, Chapter III Water Quality Objectives, Section 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The copper limit for irrigation and livestock watering supply is 5.0 mg/L and 0.5 mg/l, respectively.
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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-05-21
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
143328
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Cyfluthrin
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 143328, Cyfluthrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283271
 
Pollutant: Cyfluthrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyfluthrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143328, Cyfluthrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283293
 
Pollutant: Cyfluthrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cyfluthrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143330
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Cyhalothrin, Lambda
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 143330, Cyhalothrin, Lambda
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284112
 
Pollutant: Cyhalothrin, Lambda
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143330, Cyhalothrin, Lambda
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284110
 
Pollutant: Cyhalothrin, Lambda
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lambda-cyhalothrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143326
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Cypermethrin
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 143326, Cypermethrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283138
 
Pollutant: Cypermethrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cypermethrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143326, Cypermethrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283161
 
Pollutant: Cypermethrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cypermethrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143329
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Deltamethrin
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 143329, Deltamethrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283505
 
Pollutant: Deltamethrin
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 BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) 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 1 samples were collected, 1 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: 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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: Data for this waterbody were collected over the date range 2018-01-08 to 2018-01-08
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 143329, Deltamethrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283558
 
Pollutant: Deltamethrin
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 BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) 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 1 samples were collected, 1 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: 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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: Data for this waterbody were collected over the date range 2018-01-08 to 2018-01-08
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
143331
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Esfenvalerate/Fenvalerate
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 143331, Esfenvalerate/Fenvalerate
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283533
 
Pollutant: Esfenvalerate/Fenvalerate
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Esfenvalerate.
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 chronic criterion for esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of esfenvalerate 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 Esfenvalerate
 
Spatial Representation: The samples were collected at 1 monitoring site: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143331, Esfenvalerate/Fenvalerate
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283604
 
Pollutant: Esfenvalerate/Fenvalerate
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Esfenvalerate.
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 chronic criterion for esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of esfenvalerate 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 Esfenvalerate
 
Spatial Representation: The samples were collected at 1 monitoring site: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143313
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Fenvalerate
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 143313, Fenvalerate
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283467
 
Pollutant: Fenvalerate
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenvalerate.
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 evaluation guideline for fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143313, Fenvalerate
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283752
 
Pollutant: Fenvalerate
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fenvalerate.
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 evaluation guideline for fenvalerate is the LC50 of 1.13 ug/L for fathead minnow, Pimephales promelas. (USEPA Office of Pesticide Programs Ecotoxicity database)
Guideline Reference: OPP Pesticide Ecotoxicity Database.
 
Spatial Representation: The samples were collected at 1 monitoring site: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143323
Region 2     
Calabazas Creek (Santa Clara County)
 
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:
 
 
Line of Evidence (LOE) for Decision ID 143323, Fipronil
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283958
 
Pollutant: Fipronil
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143323, Fipronil
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283935
 
Pollutant: Fipronil
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143314
Region 2     
Calabazas Creek (Santa Clara County)
 
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 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 143314, Fipronil Desulfinyl
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284024
 
Pollutant: Fipronil Desulfinyl
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Desulfinyl.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143314, Fipronil Desulfinyl
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283857
 
Pollutant: Fipronil Desulfinyl
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Desulfinyl.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143332
Region 2     
Calabazas Creek (Santa Clara County)
 
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 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 143332, Fipronil Sulfide
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283859
 
Pollutant: Fipronil Sulfide
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143332, Fipronil Sulfide
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283920
 
Pollutant: Fipronil Sulfide
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143333
Region 2     
Calabazas Creek (Santa Clara County)
 
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 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 143333, Fipronil Sulfone
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283862
 
Pollutant: Fipronil Sulfone
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143333, Fipronil Sulfone
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284089
 
Pollutant: Fipronil Sulfone
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143324
Region 2     
Calabazas Creek (Santa Clara County)
 
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 143324, Imidacloprid
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 283995
 
Pollutant: Imidacloprid
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Imidacloprid.
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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143324, Imidacloprid
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284057
 
Pollutant: Imidacloprid
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Imidacloprid.
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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143318
Region 2     
Calabazas Creek (Santa Clara County)
 
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:
 
 
Line of Evidence (LOE) for Decision ID 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284955
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285001
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285007
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285296
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285092
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285450
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285003
 
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 WY2017 data for Calabazas Creek (Santa Clara County) 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284850
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285118
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284823
 
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 WY2017 data for Calabazas Creek (Santa Clara County) 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285344
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285025
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285050
 
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 Calabazas Creek (Santa Clara County) 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284786
 
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 Calabazas Creek (Santa Clara County) 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 285266
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143318, Oxygen, Dissolved
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 284795
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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
143334
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Permethrin
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 143334, Permethrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286567
 
Pollutant: Permethrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Permethrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143334, Permethrin
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286517
 
Pollutant: Permethrin
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Permethrin.
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 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
143322
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Pyrethroids
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:
 
 
Line of Evidence (LOE) for Decision ID 143322, Pyrethroids
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287782
 
Pollutant: Pyrethroids
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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 143322, Pyrethroids
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287537
 
Pollutant: Pyrethroids
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold 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: 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08
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
145356
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287897
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288365
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287895
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287898
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287838
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288157
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 145356, Specific Conductivity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288007
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for SpecificConductivity.
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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as municipal supply (MUN) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The water quality objective for specific conductivity is 3000 uS/cm.
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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
 
DECISION ID
143320
Region 2     
Calabazas Creek (Santa Clara County)
 
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288654
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288763
 
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 BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) 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, 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288848
 
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 BASMAA RMC Monitoring in WY2017 data for Calabazas Creek (Santa Clara County) 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, 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288562
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288522
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288770
 
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 BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) 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, 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288626
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143320, Temperature, water
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 288777
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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
143321
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Toxicity
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 143321, Toxicity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 268878
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: TST
 
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: 0 of the 1 samples collected by BASMAA RMC Monitoring in WY2018 for Calabazas Creek (Santa Clara County) exhibited toxicity. All samples met the requirements of the State Policy for Water Quality Control: Toxicity Provisions. This includes utilizing the Test of Significant Toxicity (TST) and using toxicity testing methods provided in the Provisions to assess water column 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: Ceriodaphnia dubia for Young/female, Pimephales promelas for Biomass (wt/orig indiv), Selenastrum capricornutum for Total Cell Count.
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: 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: Attainment of the water quality objective is demonstrated by conducting aquatic toxicity testing, analyzing the data using the TST statistical approach, and rejecting the null hypothesis. The null hypothesis is the following general statement: the ambient water is toxic because the response (e.g., survival, reproduction, growth) of the test organisms in the ambient water sample is less than or equal to 75 percent (chronic) or 80 percent (acute) of the test organisms’ response in the control water sample. The alternative hypothesis is the following general statement: the ambient water is not toxic because the of the test organisms in the ambient water sample is greater than 75 percent (chronic) or 80 percent (acute) of the test organisms’ response in the control water sample.
Guideline Reference: Toxicity Provisions to the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California.
 
Spatial Representation: The samples were collected at monitoring site: 205CAL018 ( Calabazas Creek south of Hwy 101 ).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08.
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 143321, Toxicity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 268808
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: TST
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by BASMAA RMC Monitoring in WY2018 for Calabazas Creek (Santa Clara County) exhibited toxicity. All samples met the requirements of the State Policy for Water Quality Control: Toxicity Provisions. This includes utilizing the Test of Significant Toxicity (TST) and using toxicity testing methods provided in the Provisions to assess water column 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: Ceriodaphnia dubia for Young/female, Pimephales promelas for Biomass (wt/orig indiv), Selenastrum capricornutum for Total Cell Count.
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: 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: Attainment of the water quality objective is demonstrated by conducting aquatic toxicity testing, analyzing the data using the TST statistical approach, and rejecting the null hypothesis. The null hypothesis is the following general statement: the ambient water is toxic because the response (e.g., survival, reproduction, growth) of the test organisms in the ambient water sample is less than or equal to 75 percent (chronic) or 80 percent (acute) of the test organisms’ response in the control water sample. The alternative hypothesis is the following general statement: the ambient water is not toxic because the of the test organisms in the ambient water sample is greater than 75 percent (chronic) or 80 percent (acute) of the test organisms’ response in the control water sample.
Guideline Reference: Toxicity Provisions to the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California.
 
Spatial Representation: The samples were collected at monitoring site: 205CAL018 ( Calabazas Creek south of Hwy 101 ).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08.
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 143321, Toxicity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 268877
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by BASMAA RMC Monitoring in WY2018 for Calabazas Creek (Santa Clara County) 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: Pimephales promelas for Survival, Chironomus dilutus for Survival.
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: 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: 205CAL018 ( Calabazas Creek south of Hwy 101 ).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08.
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 143321, Toxicity
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 268705
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
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: 0 of the 1 samples collected by BASMAA RMC Monitoring in WY2018 for Calabazas Creek (Santa Clara County) 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: Pimephales promelas for Survival, Chironomus dilutus for Survival.
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: 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: 205CAL018 ( Calabazas Creek south of Hwy 101 ).
Temporal Representation: The samples were collected between the dates of 2018-01-08 and 2018-01-08.
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
143319
Region 2     
Calabazas Creek (Santa Clara County)
 
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:
 
 
Line of Evidence (LOE) for Decision ID 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287013
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287237
 
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 Calabazas Creek (Santa Clara County) 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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286738
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286872
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2012 data for Calabazas Creek (Santa Clara County) 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R00099 (Calabazas Creek - Midway between Bollinger and Blaney-205R00099).
Temporal Representation: The samples were collected between the dates of 2012-05-17 and 2012-05-17
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286923
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
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 WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R00547 (Calabazas Creek Pomeroy Elementary School Baseball Field-205R00547).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287381
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286966
 
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 Calabazas Creek (Santa Clara County) 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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287439
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R03875 (Calabazas Creek at South End of Creekside Park).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287027
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 WY2018 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205CAL018 (Calabazas Creek south of Hwy 101).
Temporal Representation: The samples were collected between the dates of 2018-05-21 and 2018-05-21
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287071
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 WY2017 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287612
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2017 data for Calabazas Creek (Santa Clara County) 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R03443 (Calabazas Creek at HWY 101).
Temporal Representation: The samples were collected between the dates of 2017-06-01 and 2017-06-01
Environmental Conditions:
QAPP Information: EOA, Inc., Applied Marine Sciences, Armand Ruby Consulting . 2016. BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan.
QAPP Information Reference(s): BASMAA Regional Monitoring Coalition Creek Status and Pesticides & Toxicity Monitoring Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287273
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2013 data for Calabazas Creek (Santa Clara County) 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287131
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 WY2013 data for Calabazas Creek (Santa Clara County) to determine beneficial use support and results are as follows: 1 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: 205R00627 (Calabazas Creek at Patrick Henry Dr.-205R00627).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287751
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2018 data for Calabazas Creek (Santa Clara County) 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 286823
 
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 WY2018 data for Calabazas Creek (Santa Clara County) 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: 205R04266 (Calabazas Creek downstream Prospect Rd).
Temporal Representation: The samples were collected between the dates of 2018-05-02 and 2018-05-02
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 143319, pH
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 287566
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed BASMAA RMC Monitoring in WY2016 data for Calabazas Creek (Santa Clara County) 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 3.3.22 Constituents of Concern for Municipal and Agricultural Water Supplies states: At a minimum, surface waters designated for use as agricultural supply (AGR) shall not contain concentrations of constituents in excess of the levels specified in Table 3-6. The limit for pH ranges from 4.5-9.0.
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: 205R02538 (Downstream Padero Court).
Temporal Representation: The samples were collected between the dates of 2016-05-18 and 2016-05-18
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
97126
Region 2     
Calabazas Creek (Santa Clara County)
 
Pollutant: Diazinon
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Original
Sources: A Source Unknown
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: 303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed. The USEPA final decision on the 2006 303(d) list was to move this listing to the being addressed by a USEPA approved TMDL portion of the 303(d) list, because the San Francisco Bay Urban Creeks Diazinon TMDL was approved by USEPA on 5/16/07 (USEPA, 2007).
 
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 97126, Diazinon
Region 2     
Calabazas Creek (Santa Clara County)
 
LOE ID: 95798
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: 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):