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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Jahant Slough (San Joaquin County)
Water Body ID: CAR5312000020190718025605
Water Body Type: River & Stream
 
DECISION ID
160220
Region 5     
Jahant Slough (San Joaquin County)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2020)
Revision Status Revised
Sources: A Source Unknown
TMDL Priority: Low
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Four lines of evidence are available in the administrative record to assess this pollutant. Eighteen of 18 samples exceed the water quality objective for COLD and SPWN.

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

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Eighteen of 18 samples exceed the water quality objective for COLD and SPWN and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 160220, Oxygen, Dissolved
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 208382
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Fish Spawning
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 160220, Oxygen, Dissolved
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 208271
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 160220, Oxygen, Dissolved
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 332212
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 11 of 11 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as COLD is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 531XJSACL (Jahant Slough @ Cherokee Ln).
Temporal Representation: The samples were collected between the dates of 2017-01-05 and 2019-05-21
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
Line of Evidence (LOE) for Decision ID 160220, Oxygen, Dissolved
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 332134
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Fish Spawning
 
Number of Samples: 11
Number of Exceedances: 11
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 11 of 11 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The minimum dissolved oxygen concentration for waters designated as SPWN is 7.0 mg/L. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin Basin)
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 531XJSACL (Jahant Slough @ Cherokee Ln).
Temporal Representation: The samples were collected between the dates of 2017-01-05 and 2019-05-21
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
 
DECISION ID
160222
Region 5     
Jahant Slough (San Joaquin County)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2020)
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 160222, Temperature, water
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 332986
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans).
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site: 531XJSACL (Jahant Slough @ Cherokee Ln).
Temporal Representation: The samples were collected between the dates of 2017-01-05 and 2019-05-21
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
Line of Evidence (LOE) for Decision ID 160222, Temperature, water
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 230580
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 160222, Temperature, water
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 230718
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Migration
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 160222, Temperature, water
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 230719
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Fish Spawning
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Water Board that such alteration in temperature does not adversely affect beneficial uses (Sacramento-San Joaquin River Basin Plans.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
 
DECISION ID
168334
Region 5     
Jahant Slough (San Joaquin 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 168334, Toxicity
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 347498
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 5 samples collected by San Joaquin County Delta Water Quality Coalition for Jahant Slough (San Joaquin 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: Selenastrum capricornutum for Total Cell Count.
Data Reference: Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
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: 531XJSACL ( Jahant Slough @ Cherokee Ln ).
Temporal Representation: The samples were collected between the dates of 2019-01-08 and 2019-05-21.
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
 
DECISION ID
160221
Region 5     
Jahant Slough (San Joaquin County)
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2020)
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 160221, pH
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 332427
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ from the Irrigated Lands Regulatory Program for the 2026 Integrated Report in Region 5
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 531XJSACL (Jahant Slough @ Cherokee Ln).
Temporal Representation: The samples were collected between the dates of 2017-01-05 and 2019-05-21
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
Line of Evidence (LOE) for Decision ID 160221, pH
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 228409
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 160221, pH
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 229334
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition
 
Line of Evidence (LOE) for Decision ID 160221, pH
Region 5     
Jahant Slough (San Joaquin County)
 
LOE ID: 228885
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 7
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Joaquin County Delta Water Quality Coalition data for Jahant Slough (San Joaquin County) to determine beneficial use support and results are as follows: 0 of 7 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Sediment, Toxicity, Water data for the 2020/2022 integrated report in Region 5.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Valley Region Sacramento River Basin and San Joaquin River Basin: pH should not be lower than 6.5 or higher than 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the California Regional Water Quality Control Board Central Valley Region, Sacramento and San Joaquin River Basins; Fifth Edition. Revised May 2018 (with approved amendments)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (531XJSACL)
Temporal Representation: The samples were collected between the dates of 2015-01-20 and 2016-05-17
Environmental Conditions:
QAPP Information: Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2010. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0) ., Prepared by Michael L. Johnson LLC for the Irrigated Lands Program. 2015. Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0) ., Michael L. Johnson LLC. 2015. Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition .
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 2.0)
QAPP Information Reference(s): Quality Assurance Project Plan For Monitoring By The San Joaquin County & Delta Water Quality Coalition (Revision 3.0)
QAPP Information Reference(s): Quality Assurance Project Plan for Monitoring By the San Joaquin County & Delta Water Quality Coalition