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Waterbody profile

Official Water Board record · 2026 cycle

Santa Maria River

Waterbody ID (WBID)
CAR3121003020011228103528
County / counties
San Luis Obispo, Santa Barbara
Regional Water Board
Regional Board 3 - Central Coast Region
Waterbody type
River & Stream
Condition category
Category 5 — 303(d) listed, TMDL required
Integrated Report cycle
2026

303(d) listings (29)

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
ArsenicMetals109723List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
Benthic Community EffectsOther Cause131917List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
ChlorideSALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES109732Do Not Delist from 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
ChlorpyrifosPesticides109734Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
Cyhalothrin, LambdaPesticides109801List on 303(d) list (being addressed by USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
CypermethrinPesticides144899Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
DDD (Dichlorodiphenyldichloroethane)Pesticides130074Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
DDE (Dichlorodiphenyldichloroethylene)Pesticides130144Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
DDT (Dichlorodiphenyltrichloroethane)Pesticides129840Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
DiazinonPesticides109737Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
DieldrinPesticides109739Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
EndrinPesticides109744Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
ImidaclopridPesticides109785List on 303(d) list (TMDL required list)Revised5A TMDL still requiredHigh
LeadMetals109749List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
LinuronPesticides109751List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
MalathionPesticides109752Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
ManganeseMetals109753List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
NitrateNutrients128189Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Nitrogen Compounds and Orthophosphate TMDL
OxyfluorfenPesticides129921List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
PrometrynPesticides129920List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
PyrethroidsPesticides144898List on 303(d) list (being addressed by USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
SeleniumMetals109773List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
SodiumSALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES109776Do Not Delist from 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
Specific ConductivitySALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES126421List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
Temperature, waterOther Cause126171List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
Total Dissolved SolidsSALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES109777List on 303(d) list (TMDL required list)Revised5A TMDL still requiredLow
ToxaphenePesticides85423List on 303(d) list (being addressed by USEPA approved TMDL)Original5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
ToxicityTotal Toxics109778Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)Revised5B Addressed by USEPA-approved TMDLSanta Maria River Watershed Toxicity and Pesticides TMDL
TurbiditySediment109780Do Not Delist from 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
CAR3121003020011228103528
CALWNUM
3312.100101, 3312.100300
WBD code
180600070606, 180600080404, 180600080602, 180600080603
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
24.59 Miles

Derived facility associations

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

Derived
Byron Winery

Santa Maria · Notice of Non-Applicability

derived_watershed_association

Derived by California Stormwater Intelligence

Calportland Construction

Santa Maria · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Cambria Winery

Santa Maria · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Curation Foods

Guadalupe · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Hanson Aggregates

Santa Maria · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Household Hazardous Waste Collection Facility at the SMRL

Santa Maria · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

Mid State Concrete Products

Santa Maria · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Nipomo Bin

Nipomo · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

ReadyRefresh Santa Maria

Nipomo · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Santa Maria Transfer Station

Nipomo · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Simplot Grower Solutions Guadalupe

Guadalupe · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

SMOOTH Inc

Santa Maria · No Exposure Certification

derived_watershed_association

Derived by California Stormwater Intelligence

Taylor Farms Retail Inc

Guadalupe · Notice of Intent

derived_watershed_association

Derived by California Stormwater Intelligence

Vaquero Energy Inc

Santa Maria · 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.