Los Penasquitos Creek

2026 303(d) list Waterbody ID CAR9061000020011025112826 River & Stream Region 9 · San Diego

At a glance

2026 listing Evidence: State-published
On the 2026 303(d) list · 13 Appendix A decisions
Category 5: a TMDL is required
What a listing means
Pollutants and stressors
13 pollutants in 6 Appendix A categories
Nutrients (3) · Other Cause (1) · Pathogens (1) · Pesticides (6) · SALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES (1) · Total Toxics (1)
Listing decisions
TMDL information Evidence: State-published
13 decisions with a TMDL requirement status
Status codes as published: 5A
TMDL details
Regional Water Board
Region 9 · San Diego
River & Stream · Map
Industrial stormwater facilities
13 report it as their receiving water Evidence: identification corroborated
63 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
13
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
9 — San Diego

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 (3 decisions)

Nutrients: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
NitrogenNutrients5 Do Not Delist from 303(d) list (TMDL required list)RevisedA Source Unknown 132042
PhosphateNutrients5 List on 303(d) list (TMDL required list)OriginalA Source Unknown 69190
PhosphorusNutrients5 List on 303(d) list (TMDL required list)RevisedA Source Unknown 111715

Other Cause (1 decision)

Other Cause: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
Benthic Community EffectsOther Cause5 Do Not Delist from 303(d) list (TMDL required list)RevisedA Source Unknown Contaminated Sediments Hydromodification Illicit Connections/Illegal Hook-ups/Dry Weather Flows Unknown Nonpoint Source Unknown Point Source Urban Runoff/Storm Sewers 145050

Pathogens (1 decision)

Pathogens: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
Indicator BacteriaPathogens5 Do Not Delist from 303(d) list (TMDL required list)RevisedA Source Unknown 127888

Pesticides (6 decisions)

Pesticides: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
BifenthrinPesticides5 Do Not Delist from 303(d) list (TMDL required list)RevisedA Source Unknown 111726
CyfluthrinPesticides5 List on 303(d) list (TMDL required list)RevisedA Source Unknown 111733
Cyhalothrin, LambdaPesticides5 List on 303(d) list (TMDL required list)RevisedA Source Unknown 111735
CypermethrinPesticides5 List on 303(d) list (TMDL required list)RevisedA Source Unknown 144946
PermethrinPesticides5 List on 303(d) list (TMDL required list)RevisedA Source Unknown 130377
PyrethroidsPesticides5 List on 303(d) list (TMDL required list)RevisedA Source Unknown 144945

SALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES (1 decision)

SALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
Total Dissolved SolidsSALINITY/TOTAL DISSOLVED SOLIDS/CHLORIDES/SULFATES5 Do Not Delist from 303(d) list (TMDL required list)RevisedA Source Unknown 111720

Total Toxics (1 decision)

Total Toxics: Appendix A decisions
PollutantPollutant categoryCategoryFinal listing decisionDecision statusSourcesDecision ID
ToxicityTotal Toxics5 Do Not Delist from 303(d) list (TMDL required list)RevisedA Source Unknown 111721

TMDL information Evidence: State-published

TMDL information published for this waterbody
PollutantTMDL requirement statusTMDL projectPriorityUSEPA approval of TMDLExpected attainment
Benthic Community Effects5A— Low——
Bifenthrin5A— Low——
Cyfluthrin5A— Low——
Cyhalothrin, Lambda5A— Low——
Cypermethrin5A— Low——
Indicator Bacteria5A— Low——
Nitrogen5A— Low——
Permethrin5A— Low——
Phosphate5A— Low——
Phosphorus5A— Low——
Pyrethroids5A— Low——
Total Dissolved Solids5A— Low——
Toxicity5A— Low——

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

None published.

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

Facilities whose reported receiving water is identified as this waterbody
FacilityWDIDStatusDistance from reported locationMap
Microelectronic Pkg America9 37I012105 Terminated165 m map
Pall Filtration Separations9 37I013689 Terminated222 m map
Pall Filtration Separations9 37NEC000328 Active222 m map
Lemke Mfg9 37I000791 Terminated234 m map
Precision Engine Controls9 37I026372 Terminated280 m map
Precision Engine Controls9 37NEC012548 Active280 m map
Rayotek Scientific Inc9 37NEC000120 Terminated291 m map
Dexcom Sequence Dr9 37I028939 Terminated1.4 km map
Dexcom Sequence Dr9 37NEC002647 Terminated1.4 km map
Dexcom Sequence Dr9 37NEC016337 Active1.4 km map
Quality Systems Integrated Corp9 37I024532 Terminated1.5 km map
Quality Systems Integrated Corp9 37NEC001860 Terminated1.5 km map
Coredux USA LLC9 37I024516 Active1.6 km map

Receiving water reported by facility — waterbody identification corroborated by geographic evidence. 13 facilities.

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
Pacific Membranes Inc9 37IN601135 Undetermined85 m map
Titan Linkabit Electronics9 37I004118 Terminated120 m map
BioLegend9 37IN600864 Undetermined120 m map
All Right Storage9 37IN601669 Undetermined161 m map
Ajinomoto Althea9 37I026199 Terminated164 m map
Ajinomoto Althea9 37NEC002001 Terminated164 m map
Microelectronic Pkg America9 37I012105 Terminated165 m map
Althea Technologies9 37IN600702 Undetermined167 m map
PCI San Diego Inc9 37NEC014933 Active181 m map
Implant Sciences Corp9 37IN601692 Undetermined183 m map
Ajinomoto Althea9 37NEC006230 Terminated196 m map
Qualcomm Inc9 37I009792 Terminated212 m map
Pall Filtration Separations9 37I013689 Terminated222 m map
Pall Filtration Separations9 37NEC000328 Active222 m map
Qualified Machine Shop9 37IN600701 Undetermined224 m map
Public Storage9 37IN600759 No Action Required227 m map
Stolper International, Inc9 37IN600341 Undetermined231 m map
Integrated Microwave Corp9 37I021888 Terminated232 m map
Integrated Microwave Corp9 37NEC002242 Active232 m map
PETNET Solutions9 37IN600347 Undetermined233 m map
Lemke Mfg9 37I000791 Terminated234 m map
Pacific Plastics9 37IN600774 Undetermined234 m map
Prima Pharm Inc9 37IN600508 Undetermined246 m map
Prima Pharm Inc9 37IN600509 No Action Required246 m map
PrimaPharm Incorporated9 37IN600639 No Action Required246 m map
Precision Engine Controls9 37I026372 Terminated280 m map
Precision Engine Controls9 37NEC012548 Active280 m map
Mayflower Contract Services9 37I004682 Terminated290 m map
Laidlaw Transit Poway9 37I011798 Terminated290 m map
Rayotek Scientific Inc9 37NEC000120 Terminated291 m map
Pump Station 659 37I019089 Terminated298 m map
TDAK Medical Inc9 37IN601676 Undetermined359 m map
New English Brewing Company Incorporated9 37NEC000151 Active363 m map
Codex DNA9 37NEC006438 Terminated390 m map
Canseco, Adriana9 37NNA001952 NONA Submitted412 m map
Silica9 37IN600805 Undetermined417 m map
DYE Precision CNC Inc9 37IN601602 Undetermined469 m map
Cole Moving & Storage Co9 37I001898 Terminated485 m map
Gole Moving & Storage Co9 37I007172 Terminated485 m map
Rule Manufacturing Inc9 37IN602301 Undetermined560 m map
Pump Station 649 37I019090 Terminated580 m map
MZ3D Inc9 37I020547 Terminated592 m map
Concrete Cutting Co9 37IN600718 Undetermined599 m map
Tanox West Inc5F37IN602159 Undetermined715 m map
Biogen Idec Inc9 37I010764 Terminated716 m map
Tanox West Inc9 37I019266 Terminated716 m map
Gene Therapy Systems9 37IN600811 Undetermined752 m map
Northrop Grumman Nav Sys Div9 37I017285 Terminated753 m map
Direct Electron9 37IN602396 Undetermined762 m map
Becton Dickinson and Co9 37NEC012133 Active763 m map

63 facilities, nearest first. Page 1 of 2: next

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.