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Waterbody profile

Official Water Board record · 2026 cycle

McGrath Lake

Waterbody ID (WBID)
CAL4031100019990203110047
County / counties
Ventura
Regional Water Board
Regional Board 4 - Los Angeles Region
Waterbody type
Lake & Reservoir
Condition category
Category 5 — 303(d) listed, TMDL required
Integrated Report cycle
2026

303(d) listings (6)

Each row is one official listing decision from Appendix A of the Final 2026 California Integrated Report. Source terminology is preserved as published.

Pollutant / stressorDecision IDFinal listing decisionDecision statusTMDL requirement statusTMDL projectTMDL priority
ChlordanePesticides69421List on 303(d) list (being addressed by USEPA approved TMDL)Original5B Addressed by USEPA-approved TMDLMcGrath Lake Pesticides (25)
DDT (Dichlorodiphenyltrichloroethane)Pesticides99417Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Original5B Addressed by USEPA-approved TMDLMcGrath Lake Pesticides (25)
Dieldrin (sediment)Pesticides68968Do Not Delist from 303(d) list (TMDL required list)Original5A TMDL still requiredHigh
Indicator BacteriaPathogens69107Do Not Delist from 303(d) list (TMDL required list)Original5A TMDL still requiredLow
PCBs (Polychlorinated biphenyls) (sediment)Toxic Organics68440Do Not Delist from 303(d) list (TMDL required list)Original5A TMDL still requiredLow
ToxicityTotal Toxics68832Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Original5B Addressed by USEPA-approved TMDLMcGrath Lake Pesticides (25)

Source & provenance

Agency
California State Water Resources Control Board
Report
Final 2026 California Integrated Report
Dataset
Appendix A — 2026 303(d) List of Impaired Waters
Imported
Aug 21, 2026, 12:44 AM UTC
Waterbody ID
CAL4031100019990203110047
CALWNUM
40311000
Geometry
Official Water Board GIS (CA_WATERBOARDS_GIS_FINAL_2026)

Location

Official 2026 Water Board geometry. Demonstration facility markers are shown for context only.

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Watershed
Assessed size
19.42 Acres

Derived facility associations

Industrial stormwater facilities geographically associated with this waterbody. These are derived spatial associations, not Water Board findings.

Derived
West Montalvo

Oxnard · Notice of Intent · 0.13 km away

derived_receiving_water

Derived by California Stormwater Intelligence

West Montalvo Field

Oxnard · Notice of Intent · 0.61 km away

derived_receiving_water

Derived by California Stormwater Intelligence

Facility records are official Industrial General Permit registrations, but the association between a facility and this waterbody is derived geographically (proximity or shared HUC12 subwatershed) and is not a Water Board receiving-water determination. Where a permit carries a Water Board-stated TMDL requirement naming this water, it is listed separately above.