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Waterbody profile

Official Water Board record · 2026 cycle

Mt. Diablo Creek

Waterbody ID (WBID)
CAR2073104019990217163214
County / counties
Contra Costa
Regional Water Board
Regional Board 2 - San Francisco Bay Region
Waterbody type
River & Stream
Condition category
Category 5 — 303(d) listed, TMDL required
Integrated Report cycle
2026

303(d) listings (3)

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
Benthic Community EffectsOther Cause154164List on 303(d) list (TMDL required list)Revised5A — TMDL still required—Low
DiazinonPesticides69765List on 303(d) list (being addressed by USEPA approved TMDL)Original5B — Addressed by USEPA-approved TMDLSan Francisco Bay Urban Creeks Diazinon—
ToxicityTotal Toxics151290Do Not Delist from 303(d) list (TMDL required list)Revised5A — TMDL still required—Low

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
CAR2073104019990217163214
CALWNUM
2207.310102, 2207.310103, 2207.310104
WBD code
180500010302, 180500010401
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
13.96 Miles

Derived facility associations

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

Derived
BAY AREA CUSTOM LABORATORIES

Concord · No Exposure Certification · 0.66 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Benchmark

Concord · Notice of Intent · 0.92 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Bimbo Bakeries USA Inc Concord Sales Center

Concord · Notice of Non-Applicability

derived_watershed_association

Derived by California Stormwater Intelligence

CEMEX

Clayton · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Concord Auto Dismantlers

Concord · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Concord DC

Concord · Notice of Intent · 0.45 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Concord Ready Mix

Concord · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

County Connection

Concord · Notice of Intent · 0.71 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

FERNANDES AUTO WRECKING & TOWING INC

Concord · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

First Student Inc 12605

Concord · Notice of Intent · 0.98 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Heraeus Medical Components

Concord · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

MECS Inc

Martinez · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Military Ocean Terminal Concord

Concord · Notice of Intent · 0.26 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Pacific Instruments Inc

Concord · No Exposure Certification · 0.89 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

REACH 032 100 - Contra Costa Concord

Concord · Notice of Non-Applicability

derived_watershed_association

Derived by California Stormwater Intelligence

RESAWN INDUSTRIES LLC

Concord · Notice of Intent · 0.82 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Royal Ambulance

Concord · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

SEG Trucking

Concord · Notice of Intent · 0.48 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

SFIC

Concord · No Exposure Certification · 0.80 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Shred It Concord

Concord · No Exposure Certification · 0.29 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Union Pacific Railroad Suisun City

Suisun City · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

USS Posco Industries West Facilities

Pittsburg · 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.