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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: El Nido Canal (Merced County)
Water Body ID: CAR5357000020101101104142
Water Body Type: River & Stream
 
DECISION ID
168727
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Specific Conductivity
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Readily available data for this waterbody were not used to determine standards attainment as the status of the waterbody as a water of the United States is uncertain. The 303(d) list is authorized under the Clean Water Act and is therefore limited to waters of the United States. Data will be used to determine standards attainment during a future Integrated Report cycle if it is determined that this water body is classified as a water of the United States.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the listing status for this water body-pollutant combination should not change this cycle because of a lack of clarity in the status of this water body under the Clean Water Act.
 
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 168727, Specific Conductivity
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 345957
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_MERID data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the upper limit of the range for SpecificConductivity. Additionally, 0 of the 2 samples fall within the range, and 2 of 2 samples fall below the threshold.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference into the Water Quality Control Plan for the Sacramento and San Joaquin River Basins specifies a range for specific conductance of 900-1600 uS/cm assessed as an annual average.
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: 545MRDEDM (El Nido Dam on Mariposa Ck).
Temporal Representation: The samples were collected between the dates of 2007-10-02 and 2008-09-16
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
 
DECISION ID
166637
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Thiobencarb
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: Readily available data for this waterbody were not used to determine standards attainment as the status of the waterbody as a water of the United States is uncertain. The 303(d) list is authorized under the Clean Water Act and is therefore limited to waters of the United States. Data will be used to determine standards attainment during a future Integrated Report cycle if it is determined that this water body is classified as a water of the United States.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the listing status for this water body-pollutant combination should not change this cycle because of a lack of clarity in the status of this water body under the Clean Water Act.
 
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 166637, Thiobencarb
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 346059
 
Pollutant: Thiobencarb
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_MERID data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Thiobencarb.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary Maximum Contaminant Level for thiobencarb by reference in the Water Quality Control Plan for the Sacramento and San Joaquin River Basins is 0.001 mg/L assessed as an annual average.
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: 545MRDEDM (El Nido Dam on Mariposa Ck).
Temporal Representation: The samples were collected between the dates of 2007-10-02 and 2008-09-16
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
 
DECISION ID
166636
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Total Dissolved Solids
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: LOEs for this waterbody-pollutant combination from previous cycles were reassessed according to a new assessment method. 

Readily available data for this waterbody were not used to determine standards attainment as the status of the waterbody as a water of the United States is uncertain. The 303(d) list is authorized under the Clean Water Act and is therefore limited to waters of the United States. Data will be used to determine standards attainment during a future Integrated Report cycle if it is determined that this water body is classified as a water of the United States.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the listing status for this water body-pollutant combination should not change this cycle because of a lack of clarity in the status of this water body under the Clean Water Act.
 
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 166636, Total Dissolved Solids
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 346074
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed ILRP_MERID data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the upper limit of the range for Total Dissolved Solids. Additionally, 0 of the 2 samples fall within the range, and 2 of 2 samples fall below the threshold.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Secondary MCL that is incorporated by reference into the Water Quality Control Plan for the Sacramento and San Joaquin River Basins specifies a range for total dissolved solids of 500-1000 mg/L assessed as an annual average.
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: 545MRDEDM (El Nido Dam on Mariposa Ck).
Temporal Representation: The samples were collected between the dates of 2007-10-02 and 2008-01-09
Environmental Conditions:
QAPP Information: QAPP Reference for Irrigated Lands Regulatory Program
QAPP Information Reference(s): QAPP Reference for Irrigated Lands Regulatory Program
 
 
DECISION ID
89363
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Alachlor
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89363, Alachlor
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63327
 
Pollutant: Alachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: A total of 4 individual whole water samples were collected; 0 of 4 samples exceeded the objective (2 ug/L).
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for alachlor is 2 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
89364
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Atrazine
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89364, Atrazine
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63329
 
Pollutant: Atrazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: A total of 4 individual whole water samples were collected; 0 of 4 samples exceeded the objective (1 ug/L).
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California Maximum Contaminant Level for atrazine is 0.001 mg/L (Title 22 of the California Code of Regulations ).
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
89365
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Glyphosate
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89365, Glyphosate
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63334
 
Pollutant: Glyphosate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: A total of 4 individual whole water samples were collected; 0 of 4 samples exceeded the evaluation guideline (700 ug/L).
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Glyphosate is 700 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
89366
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Metolachlor
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89366, Metolachlor
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63336
 
Pollutant: Metolachlor
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Metolachlor.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River 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. 4th ed
 
Evaluation Guideline: The National Ambient Water Quality criterion for Human Health and Welfare Protection of Public Health Effects (other than cancer effects) from Water & Fish Consumption for metolachlor is 44 µg/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
89445
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Molinate
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89445, Molinate
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63339
 
Pollutant: Molinate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Molinate.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Molinate is 20 ug/L .
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
89446
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Norflurazon
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89446, Norflurazon
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63340
 
Pollutant: Norflurazon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Norflurazon.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River 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. 4th ed
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for norflurazon is 280 µg/L.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
100497
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Oryzalin
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 100497, Oryzalin
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63341
 
Pollutant: Oryzalin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Oryzalin.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (Water Quality Control Plan, Central Valley Region, Sacramento River Basin and San Joaquin River 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. 4th ed
 
Evaluation Guideline: Based on USEPA IRIS reference dose (RfD) as a drinking water level, the drinking water health advisory level for Oryzalin is 35 µg/L.
Guideline Reference: IRIS Database Calculations (summary)
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):
 
 
DECISION ID
89447
Region 5     
El Nido Canal (Merced County)
 
Pollutant: Simazine
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)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Data for this water segment-pollutant combination were received by the State Water Resources Control Board as part of the data solicitation for the 2014 Integrated Report Cycle. These data were not assessed as part of the 2014 Integrated Report.
 
Regional Board Decision Recommendation: Data for this water segment - pollutant combination were not assessed by RWQCB staff during the 2014 Integrated Report cycle. RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list at this time. These data will be assessed by RWQCB staff during a future Integrated Report cycle to determine the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 89447, Simazine
Region 5     
El Nido Canal (Merced County)
 
LOE ID: 63345
 
Pollutant: Simazine
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for El Nido Canal (Merced County) to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Simazine.
Data Reference: Data for Various Pollutants in Merced Irrigation District, 2005-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California primary maximum contaminant level for Simazine is 4 ug/L.
Objective/Criterion Reference: Maximum Contaminant Levels for organic and inorganic chemicals. CCR Title 22
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for El Nido Canal (Merced County) was collected at 1 monitoring site [El Nido Canal Spill to Chowchilla Slough - 545MRDECC]
Temporal Representation: Data was collected over the time period 8/1/2007-9/16/2008.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: Data for this line of evidence was collected as part of the Irrigated Lands Regulatory Program.
QAPP Information Reference(s):