Final California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Castroville Slough
Water Body ID: CAE3091200020200717048074
Water Body Type: Coastal & Bay Shoreline
 
DECISION ID
126269
Region 3     
Castroville Slough
 
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: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy.

A total of three lines of evidence are available in the administrative record to assess this pollutant. A total of four of 25 samples exceed the water quality objective for the cold freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of four of 25 samples exceed the water quality objective for the cold freshwater habitat beneficial use. This does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board 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 126269, Temperature, water
Region 3     
Castroville Slough
 
LOE ID: 217031
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 1 of 2 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2011-05-07 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 126269, Temperature, water
Region 3     
Castroville Slough
 
LOE ID: 228199
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 2 of 12 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 126269, Temperature, water
Region 3     
Castroville Slough
 
LOE ID: 228196
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 1 of 11 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
 
DECISION ID
125777
Region 3     
Castroville Slough
 
Pollutant: Nitrate
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.11 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Under section 3.11, additional lines of evidence are necessary to support a listing decision.

Ten lines of evidence are available in the administrative record to assess this pollutant. Eight of the 22 Nitrate/Nitrite samples and 12 of the 21 nitrogen, nitrate samples exceed the evaluation guideline used to interpret the narrative water quality objective for bio-stimulatory substances (Central Coast Region Technical Report, 2010). In addition, and in accordance with section 3.11 of the Listing Policy, there is supporting evidence that nitrate causes or contributes to an bio-stimulatory responses. This waterbody segment is also on the CWA section 303(d) List for dissolved oxygen.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eight of the 22 Nitrate/Nitrite samples and 12 of the 21 nitrogen, nitrate samples exceed the evaluation guideline used to interpret the narrative water quality objective for bio-stimulatory substances (Central Coast Region Technical Report, 2010), and there is the dissolved oxygen measurements support the conclusion that nitrate contributes to or causes a bio-stimulatory effect in this waterbody in accordance with section 3.11 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228169
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 11 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-06-25 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228204
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 4 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-07-24
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228137
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 11 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-06-25 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228138
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 11 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228136
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 4 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-07-24
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228203
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 11 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228202
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 5 of 11 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-09-28
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 172353
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 6 of 6 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2011-05-07 and 2016-05-07
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 172105
 
Pollutant: Nitrogen, Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 6 of 6 samples exceeded the water quality threshold for Nitrate as N.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2011-05-07 and 2016-05-07
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 125777, Nitrate
Region 3     
Castroville Slough
 
LOE ID: 228201
 
Pollutant: Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 5 of 11 samples exceeded the water quality threshold for Nitrate + Nitrite as N.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.
Guideline Reference: Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-09-28
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
 
DECISION ID
115416
Region 3     
Castroville Slough
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy.

A total of 12 lines of evidence are available in the administrative record to assess this pollutant. A total of 15 of 32 samples exceed the water quality objective for the cold freshwater habitat beneficial use, 11 of 32 samples exceed the water quality objective for the estuarine habitat beneficial use, 15 of 32 samples exceed the water quality objective for the fish spawning beneficial use and 11 of 32 samples exceed the water quality objective for the water contact recreation beneficial use.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of 15 of 32 samples exceed the water quality objective for the cold freshwater habitat beneficial use, 11 of 32 samples exceed the water quality objective for the estuarine habitat beneficial use, 15 of 32 samples exceed the water quality objective for the fish spawning beneficial use and 11 of 32 samples exceed the water quality objective for the water contact recreation beneficial use. This exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228186
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 8 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228188
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228139
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 11 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228187
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 4 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228143
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 16
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 11 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228185
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 14
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 4 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228184
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 14
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 3 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 228140
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine Habitat
 
Number of Samples: 16
Number of Exceedances: 8
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 8 of 16 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-06-19 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 175425
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
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 MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 175550
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Estuarine 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 MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/L at any time for waters not mentioned by a specific beneficial use (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 175422
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115416, Oxygen, Dissolved
Region 3     
Castroville Slough
 
LOE ID: 175573
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
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 MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
 
DECISION ID
115417
Region 3     
Castroville Slough
 
Pollutant: pH
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: No Source Analysis Available
Expected TMDL Completion Date: 2035
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the Clean Water Act (CWA) section 303(d) List under section 3.2 of the Listing Policy.

A total of 12 lines of evidence are available in the administrative record to assess this pollutant. A total of three of 25 samples exceed the water quality objective for the cold freshwater habitat beneficial use, eight of 25 samples exceed the water quality objective for the non-contact recreation beneficial use, three of 25 samples exceed the water quality objective for the warm freshwater habitat beneficial use and eight of 25 samples exceed the water quality objective for the water contact recreation beneficial use.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. A total of three of 25 samples exceed the water quality objective for the cold freshwater habitat beneficial use, eight of 25 samples exceed the water quality objective for the non-contact recreation beneficial use, three of 25 samples exceed the water quality objective for the warm freshwater habitat beneficial use and eight of 25 samples exceed the water quality objective for the water contact recreation beneficial use. This exceeds the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228194
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 11
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 5 of 11 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228198
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 2 of 11 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228191
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 2 of 11 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228193
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 1 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228190
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 1 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228192
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 1 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228195
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 11
Number of Exceedances: 5
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 5 of 11 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 178146
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 178648
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 178147
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 177848
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
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 MBNMS Snapshot Day data for Castroville Slough to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MOROC-31)
Temporal Representation: The samples were collected between the dates of 2012-05-05 and 2013-05-04
Environmental Conditions:
QAPP Information: Monterey Bay NMS. 2003. California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP).
QAPP Information Reference(s): California Coast Wide Snapshot Day 2003 Quality Assurance Project Plan (QAPP)
 
Line of Evidence (LOE) for Decision ID 115417, pH
Region 3     
Castroville Slough
 
LOE ID: 228189
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed MBNMS_Proposition84_Projects data for Castroville Slough to determine beneficial use support and results are as follows: 1 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, Water data for the 2020/2022 integrated report in Region 3.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for cold fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (306-MC-CCWG-RRX)
Temporal Representation: The samples were collected between the dates of 2018-07-02 and 2018-12-10
Environmental Conditions:
QAPP Information: Monterey Bay Sanctuary Foundation. 2014. QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)., Monterey Bay Sanctuary. 2014. Salinas Valley Irrigation and Nutrient Management Program.
QAPP Information Reference(s): QAPP for Salinas Valley Irrigation and Nutrient Management Program - Site Effectiveness Monitoring Strategy for Implementation Projects (Proposition 84 Grant No. 12-414-553)