Malibu Lagoon

2026 303(d) list Waterbody ID CAE4042100019990201160355 Estuary Region 4 · Los Angeles

At a glance

2026 listing Evidence: State-published
On the 2026 303(d) list · 6 Appendix A decisions
Category 5: a TMDL is required
What a listing means
Pollutants and stressors
6 pollutants in 3 Appendix A categories
Nutrients (1) · Other Cause (2) · Pathogens (3)
Listing decisions
TMDL information Evidence: State-published
6 decisions with a TMDL requirement status; 5 name a TMDL project
Status codes as published: 5A, 5B
TMDL details
Regional Water Board
Region 4 · Los Angeles
Estuary · Map
Industrial stormwater facilities
0 report it as their receiving water Evidence: identification corroborated
1 within 1 km Evidence: geographic proximity
Neither count establishes a discharge · Facilities

What a 303(d) listing means

The Clean Water Act section 303(d) list names waters that do not meet water quality standards for one or more pollutants or stressors. California publishes it in the Integrated Report; this page shows the 2026 decisions from Appendix A as published.

2026 listing status Evidence: State-published

On the 2026 303(d) list
Yes
Appendix A decisions
6
Integrated Report category
5 (a TMDL is required)
Listing cycle
2026
State Board adoption
2026-02-03 (Resolution 2026-0005)
USEPA approval
not confirmed — submittal letter to USEPA published; no approval found on the report page (checked 2026-10-22)
Regional Water Board
4 — Los Angeles

Published by the State Water Resources Control Board (2026 California Integrated Report, Appendix A). Listing status is taken from Appendix A only. A listing describes the condition of this waterbody, not of any facility.

Location

Loading the waterbody shape…

Listing decisions and pollutants Evidence: State-published

Grouped by the Pollutant Category published in Appendix A. Pollutant names, categories and decisions are exactly as published.

Nutrients (1 decision)

Nutrients: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
EutrophicNutrients5 List on 303(d) list (being addressed by USEPA approved TMDL)OriginalAgriculture-animal Atmospheric Deposition Golf course activities Groundwater Loadings Irrigated Crop Production Major Municipal Point Source-dry and/or wet weather discharge Onsite Wastewater Systems (Septic Tanks) Urban Runoff/Storm Sewers 69987

Other Cause (2 decisions)

Other Cause: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
Benthic Community EffectsOther Cause5 Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)OriginalA Source Unknown 99794
pHOther Cause5 Do Not Delist from 303(d) list (TMDL required list)OriginalA Source Unknown 68414

Pathogens (3 decisions)

Pathogens: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
Indicator BacteriaPathogens5 List on 303(d) list (being addressed by USEPA approved TMDL)OriginalNonpoint Source Point Source 69576
Swimming RestrictionsPathogens5 List on 303(d) list (being addressed by USEPA approved TMDL)OriginalAgriculture-animal Illicit Connections/Illegal Hook-ups/Dry Weather Flows Natural Sources Onsite Wastewater Systems (Septic Tanks) Spills Surface Runoff Urban Runoff/Storm Sewers 76137
Viruses (enteric)Pathogens5 List on 303(d) list (being addressed by USEPA approved TMDL)OriginalAgriculture-animal Illicit Connections/Illegal Hook-ups/Dry Weather Flows Natural Sources Onsite Wastewater Systems (Septic Tanks) Spills Surface Runoff Urban Runoff/Storm Sewers 76135

TMDL information Evidence: State-published

TMDL information published for this waterbody
PollutantTMDL requirement statusTMDL projectPriorityUSEPA approval of TMDLExpected attainment
Benthic Community Effects5BMalibu Lagoon Benthic Comm. Effects (71) —2013-07-02—
Eutrophic5BMalibu Creek Nutrients (50) —2003-03-21—
Indicator Bacteria5BMalibu Pathogens (47 in part) —2006-01-01—
pH5A— Low——
Swimming Restrictions5BMalibu Pathogens (47 in part) —2006-01-10—
Viruses (enteric)5BMalibu Pathogens (47 in part) —2006-01-10—

This is TMDL information for the waterbody. It does not establish that a TMDL applies to any particular facility. Facility-specific TMDL requirements recorded in SMARTS appear on facility pages and are not linked to this waterbody until reviewed.

HUC12 watersheds

Published with the listing Evidence: publisher-reported

Overlapping the waterbody's shape Evidence: spatial

Industrial stormwater facilities

Evidence: identification corroborated

Shows: the facility named this waterbody as its receiving water in SMARTS, and the name and the facility's location are consistent with it. Does not establish: a discharge pathway, a discharge of any pollutant, or a cause of the listing.

Evidence: geographic proximity

Shows: the facility's reported location is within 1 km of the waterbody's mapped shape. Does not establish: that the facility discharges to this waterbody, or any other relationship.

Report this waterbody as their receiving water Evidence: identification corroborated

No facility's reported receiving water is identified as this waterbody.

Within 1 km of a facility's reported location Evidence: geographic proximity

Spatial proximity only; discharge pathway not established. Being near this waterbody does not mean a facility discharges to it.

Facilities whose reported location is within 1 km of this waterbody
FacilityWDIDStatusDistanceMap
Malibu Masonry Supply Inc4 19I019751 Terminated185 m map

1 facility, nearest first.

Sources and provenance

Sources behind this page
InformationSourceRetrieved
Watershed Boundary Dataset HU2 GeoPackages 15, 16, 18 (WBDHU12)USGS2026-10-22
2026 California Integrated Report, Appendix A: 2026 303(d) List (final)SWRCB2026-10-22
Final_2026_Rivers_and_Streams + Final_2026_Lakes_and_Reservoirs (FeatureServer 0)SWRCB GIS2026-10-22
SMARTS TMDL requirementsSMARTS2026-10-21

Relationships computed 2026-10-22 (facility_huc12/1, proximity/1, receiving_water/2, tmdl_reference/1, waterbody_huc12_ovl/1, waterbody_huc12_pub/1).

Integrated Report categories: 5, a TMDL is required; 4a, addressed by a USEPA-approved TMDL; 4b, addressed by other pollution control requirements; 4c, impairment not caused by a pollutant.