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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Z Drain (Yolo County)
Water Body ID: CAR5100000020101028094010
Water Body Type: River & Stream
 
DECISION ID
89416
Region 5     
Z Drain (Yolo 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)(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 89416, Specific Conductivity
Region 5     
Z Drain (Yolo County)
 
LOE ID: 72376
 
Pollutant: Specific Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Ag Waiver data for Z Drain (Yolo County) to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for Conductivity(Us).
Data Reference: Data for Various Pollutants in Sacramento Valley Water Quality Coalition, 2005-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The California secondary maximum contaminant levels for electrical conductivity provide a range of values including a recommended level (900 uS/cm), an upper level (1,600 uS/cm) and a short-term level (2,200 uS/cm). The recommended level of 900 uS/cm was used as it is protective of all drinking water uses.
Objective/Criterion Reference: Secondary Maximum Contaminant Levels and Compliance. CCR Title 22 section 64449.
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Z Drain (Yolo County) was collected at 1 monitoring site [Z-Drain (Dixon RCD) - 511XZDDIX]
Temporal Representation: Data was collected over the time period 2/11/2007-8/18/2009.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: The Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition was followed.
QAPP Information Reference(s): Quality Assurance Project Plan for Sacramento Valley Water Quality Coalition.