Serrano Creek
2026 303(d) list Waterbody ID CAR8011100020080921203908 River & Stream Region 8 · Santa Ana
At a glance
- 2026 listing Evidence: State-published
- On the 2026 303(d) list · 5 Appendix A decisions
- Category 5: a TMDL is required
- What a listing means
- Pollutants and stressors
- 5 pollutants in 4 Appendix A categories
- Nutrients (1) · Other Cause (2) · Pathogens (1) · Total Toxics (1)
- Listing decisions
- TMDL information Evidence: State-published
- 5 decisions with a TMDL requirement status
- Status codes as published: 5A
- TMDL details
- Industrial stormwater facilities
- 9 report it as their receiving water Evidence: identification corroborated
- 136 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.
- A listing describes the condition of the waterbody. It does not identify which sources cause the impairment, and it does not by itself place a requirement on any particular facility.
- Listed waters do not all have the same status. The Integrated Report category says how an impairment is being addressed: 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. This waterbody's decisions are in category 5.
- TMDL requirement status values (such as 5A or 5B) are shown exactly as published in Appendix A.
2026 listing status Evidence: State-published
- On the 2026 303(d) list
- Yes
- Appendix A decisions
- 5
- 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
- 8 — Santa Ana
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
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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)
| Pollutant | Pollutant category | Category | Final listing decision | Decision status | Sources | Decision ID |
|---|---|---|---|---|---|---|
| Ammonia (Unionized) | Nutrients | 5 | Do Not Delist from 303(d) list (TMDL required list) | Original | A Source Unknown | 73597 |
Other Cause (2 decisions)
| Pollutant | Pollutant category | Category | Final listing decision | Decision status | Sources | Decision ID |
|---|---|---|---|---|---|---|
| Benthic Community Effects | Other Cause | 5 | Do Not Delist from 303(d) list (TMDL required list) | Revised | A Source Unknown | 152851 |
| pH | Other Cause | 5 | Do Not Delist from 303(d) list (TMDL required list) | Revised | A Source Unknown | 133307 |
Pathogens (1 decision)
| Pollutant | Pollutant category | Category | Final listing decision | Decision status | Sources | Decision ID |
|---|---|---|---|---|---|---|
| Indicator Bacteria | Pathogens | 5 | Do Not Delist from 303(d) list (TMDL required list) | Revised | A Source Unknown | 149178 |
Total Toxics (1 decision)
| Pollutant | Pollutant category | Category | Final listing decision | Decision status | Sources | Decision ID |
|---|---|---|---|---|---|---|
| Toxicity | Total Toxics | 5 | List on 303(d) list (TMDL required list) | Original | A Source Unknown | 96449 |
TMDL information Evidence: State-published
| Pollutant | TMDL requirement status | TMDL project | Priority | USEPA approval of TMDL | Expected attainment |
|---|---|---|---|---|---|
| Ammonia (Unionized) | 5A | — | Low | — | — |
| Benthic Community Effects | 5A | — | Low | — | — |
| Indicator Bacteria | 5A | — | Low | — | — |
| pH | 5A | — | Low | — | — |
| Toxicity | 5A | — | 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
- Upper San Diego Creek 180702040102
Overlapping the waterbody's shape Evidence: spatial
- Upper San Diego Creek 180702040102 also published
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
| Facility | WDID | Status | Distance from reported location | Map |
|---|---|---|---|---|
| XPO Logistics Freight Inc UIV | 8 30I006454 | Active | 74 m | map |
| Semi Kinetics | 8 30NEC003497 | Active | 93 m | map |
| Bio Rad Laboratories | 8 30I025517 | Active | 99 m | map |
| Applied Medical Resources | 8 30NEC000726 | Active | 170 m | map |
| Panasonic | 8 30NEC003081 | Active | 381 m | map |
| Westamerica Communications Inc | 8 30NEC000846 | Active | 484 m | map |
| Teva Parenteral Medicines Inc | 8 30I018659 | Terminated | 506 m | map |
| Herbalife Commercentre Drive | 8 30I031091 | Active | 1.1 km | map |
| Herbalife Manufacturing LLC | 8 30I026809 | Active | 1.6 km | map |
Receiving water reported by facility — waterbody identification corroborated by geographic evidence. 9 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.
| Facility | WDID | Status | Distance | Map |
|---|---|---|---|---|
| Par Pharmaceutical | 8 30NEC005872 | Terminated | 307 m | map |
| Forma Life Sciences | 8 30NEC015684 | Active | 308 m | map |
| Sun Ten Laboratories | 8 30NEC007193 | Active | 312 m | map |
| Saddleback Valley Ornamental Iron Inc | 8 30NEC001180 | Active | 321 m | map |
| Bivar Inc | 8 30NEC015149 | Active | 327 m | map |
| Tropitone Furniture Co Inc | 8 30I000175 | Terminated | 339 m | map |
| Tropitone Furniture Co Inc | 8 30NEC002854 | Terminated | 339 m | map |
| Medtronic | 8 30NEC004875 | Terminated | 341 m | map |
| Bioray Inc | 8 30NEC015825 | Active | 347 m | map |
| Medtronic | 8 30IN604096 | NEC Required | 348 m | map |
| Medtronic | 8 30NEC003892 | Terminated | 348 m | map |
| Neo Labs Pharma | 8 30NEC016301 | Active | 361 m | map |
| Medtronic | 8 30NEC004874 | Terminated | 365 m | map |
| Medennium Inc | 8 30NEC006346 | Active | 365 m | map |
| Tropitone Furniture Co Inc | 8 30NEC003992 | Terminated | 366 m | map |
| Velco Tool & Die Inc | 8 30IN608116 | Terminated | 367 m | map |
| Velco Tool & Die Inc | 8 30NEC014472 | Active | 367 m | map |
| Meggitt Orange County Inc | 8 30IN606092 | NOI Required | 368 m | map |
| Meggitt Orange County Inc | 8 30I028910 | Active | 369 m | map |
| Panasonic | 8 30NEC003081 | Active | 381 m | map |
| Huck Int Inc | 8 30I002379 | Terminated | 384 m | map |
| Camisasca Automotive Manufacturing Inc | 8 30NEC002545 | Active | 387 m | map |
| FUTEK Advanced Sensor Technology | 8 30NEC015870 | Active | 395 m | map |
| IMEX Vision LLC | 8 30NEC015598 | Active | 397 m | map |
| Advantest Test Solutions | 8 30NEC013044 | Active | 405 m | map |
| Carr Manufacturing Company Inc | 8 30NEC002351 | Terminated | 409 m | map |
| Meggitt Defense Systems Inc | 8 30I021662 | Terminated | 439 m | map |
| Meggitt Defense Systems Inc | 8 30NEC000570 | Active | 439 m | map |
| DHL Express | 9 30I015683 | Terminated | 440 m | map |
| DHL Express | 9 30I019175 | Terminated | 440 m | map |
| Ushio America Inc | 8 30NEC002358 | Active | 445 m | map |
| Dynacast Inc | 8 30I014348 | Active | 446 m | map |
| Camisasca Manufacturing | 8 30NEC002438 | Active | 450 m | map |
| Freedom Chemical Corporation | 8 30IN608113 | No Action Required | 466 m | map |
| Freedom Chemical Corporation | 8 30NEC014481 | Active | 466 m | map |
| Westamerica Communications Inc | 8 30NEC000846 | Active | 484 m | map |
| El Toro DC | 8 30I019009 | Terminated | 487 m | map |
| Radiant Robotics LLC | 8 30NEC015912 | Active | 505 m | map |
| Teva Parenteral Medicines Inc | 8 30I018659 | Terminated | 506 m | map |
| Biowy Corporation | 8 30NEC009444 | Active | 528 m | map |
| The Young Engineers Inc | 8 30NEC002548 | Terminated | 532 m | map |
| Image Options | 8 30I024496 | Terminated | 535 m | map |
| ICP west | 8 30I020176 | Terminated | 536 m | map |
| International Polymer Solutions Inc | 8 30NEC010480 | Terminated | 540 m | map |
| Los Alisos Water Dist | 8 30I000740 | Terminated | 543 m | map |
| Irvine Ranch Water District | 8 30I016556 | Terminated | 543 m | map |
| CardLogix Corp | 8 30NEC006088 | Terminated | 549 m | map |
| Stason Pharmaceuticals Inc | 8 30NEC006471 | Active | 560 m | map |
| Gatekeeper Systems Inc | 9 30NEC013108 | Active | 568 m | map |
| The Young Engineers Inc | 8 30NEC010662 | Active | 568 m | map |
Sources and provenance
| Information | Source | Retrieved |
|---|---|---|
| Watershed Boundary Dataset HU2 GeoPackages 15, 16, 18 (WBDHU12) | USGS | 2026-10-22 |
| 2026 California Integrated Report, Appendix A: 2026 303(d) List (final) | SWRCB | 2026-10-22 |
| Final_2026_Rivers_and_Streams + Final_2026_Lakes_and_Reservoirs (FeatureServer 0) | SWRCB GIS | 2026-10-22 |
| SMARTS TMDL requirements | SMARTS | 2026-10-21 |
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.