← Impaired waters

Waterbody profile

Official Water Board record · 2026 cycle

Pilarcitos Lake

Waterbody ID (WBID)
CAL2022201020091208102331
County / counties
San Mateo
Regional Water Board
Regional Board 2 - San Francisco Bay Region
Waterbody type
Lake & Reservoir
Condition category
Category 5 — 303(d) listed, TMDL required
Integrated Report cycle
2026

303(d) listings (1)

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
MercuryMetals151597List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow

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
Sep 16, 2026, 10:56 PM UTC
Waterbody ID
CAL2022201020091208102331
CALWNUM
2202.220003
WBD code
180500060201
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
97.22 Acres

Derived facility associations

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

Derived
Amizetta

Saint Helena · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Bfi Waste Systems Ox Mountain

Half Moon Bay · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Coastside News Group Inc

Half Moon Bay · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

GenNext Technologies Inc

Half Moon Bay · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

Half Moon Bay Airport

Half Moon Bay · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Half Moon Bay Bldg Inc

Half Moon Bay · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

HMB Building Garden Supply

Half Moon Bay · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

L3Harris Randtron Antenna Systems Test Site

San Mateo · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

Otter Yogurt

Half Moon Bay · Notice of Non-Applicability

derived_watershed_association

Derived by California Stormwater Intelligence

Pilarcitos Quarry

Half Moon Bay · Notice of Intent

derived_watershed_association

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.