California Stormwater Intelligence
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Waterbody profile

Official Water Board record · 2026 cycle

Marsh Creek (in Delta Waterways; western portion)

Waterbody ID (WBID)
CAR5430002019980814110539
County / counties
Contra Costa
Regional Water Board
Regional Board 5 - Central Valley Region
Waterbody type
River & Stream
Condition category
Category 5 — 303(d) listed, TMDL required
Integrated Report cycle
2026

303(d) listings (8)

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
BifenthrinPesticides170967Do Not Delist from 303(d) list (TMDL required list)Revised5A — TMDL still required—Low
CyfluthrinPesticides170968Do Not Delist from 303(d) list (TMDL required list)Revised5A — TMDL still required—Low
Cyhalothrin, LambdaPesticides170969Do Not Delist from 303(d) list (TMDL required list)Revised5A — TMDL still required—Low
Indicator BacteriaPathogens74016Do Not Delist from 303(d) list (TMDL required list)Original5A — TMDL still required—Low
MercuryMetals144996Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B — Addressed by USEPA-approved TMDLDelta Methylmercury TMDL Project—
PermethrinPesticides170970Do Not Delist from 303(d) list (TMDL required list)Revised5A — TMDL still required—Low
PyrethroidsPesticides170966Do Not Delist from 303(d) list (TMDL required list)Revised5A — TMDL still required—Low
ToxicityTotal Toxics117538Do 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
Aug 21, 2026, 12:44 AM UTC
Waterbody ID
CAR5430002019980814110539
CALWNUM
6544
WBD code
180400030702, 180400030803
Geometry
Official Water Board GIS (CA_WATERBOARDS_GIS_FINAL_2026)
View official Water Board fact sheet ↗Download Appendix A source file ↗

Location

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

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Watershed
—
Assessed size
12.52 Miles

Derived facility associations

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

Derived
A A Auto Parts

Brentwood · Notice of Intent · 0.74 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Amazon com Services LLC SCK8

Oakley · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Brentwood Ready Mix Plant

Brentwood · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Delta Scrap and Salvage

Oakley · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Foundation Constructors Inc

Oakley · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Golden Gate Petroleum

Brentwood · Notice of Intent · 0.89 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Groceryworks Operating Company LLC

Brentwood · Notice of Non-Applicability · 0.78 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Imperiale Beer Cafe llc

Brentwood · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

Intrepid Delivery

Brentwood · Notice of Non-Applicability

derived_watershed_association

Derived by California Stormwater Intelligence

Liberty Union High School District

Brentwood · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

MAGWATT LLC

Brentwood · No Exposure Certification · 0.35 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Marine Emporium Boat Works

Oakley · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Mike Asbill Painting

Brentwood · Notice of Non-Applicability · 0.36 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

Pena Auto Dismantler 1 LLC

Oakley · Notice of Intent · 0.85 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

TownCentre Self Storage

Brentwood · Notice of Non-Applicability · 0.36 km away

derived_nearby_in_watershed

Derived by California Stormwater Intelligence

UPS Oakley CAOAL

Oakley · 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.