United Rock Products
Active WDID 4 19I000779 Irwindale, Los Angeles County Region 4 · Los Angeles
At a glance
- Permit Evidence: SMARTS record
- Active Industrial
- Notice of Intent (WDID code I) · Permits and applications
- Location Evidence: facility-reported
- Irwindale, Los Angeles County
- Region 4 · Los Angeles · Location · Statewide map
- Receiving water
- Sawpit Creek (as reported by the facility)
- Evidence: identification corroborated Sawpit Creek Details
- Identified receiving water on the 2026 303(d) list
- Yes · 4 Appendix A decisions, category 5 Evidence: State-published
- Describes the waterbody, not this facility · Waterbody profile
- 2026 Integrated Report waters within 1.0 km Evidence: geographic proximity
- 1 waterbody; 0 on the 2026 303(d) list
- Proximity only; not a discharge pathway · Nearby waterbodies
- Monitoring results Evidence: facility-reported
- 223 distinct results, 6 reporting years (2015 to 2020)
- Most recent sample Jan 29, 2021 · Monitoring
- Compliance and enforcement records Evidence: SMARTS record
- 2 inspections · 7 violation records · 3 enforcement actions
- Counts as published in SMARTS; not a compliance determination · Details
Each label shows where a statement comes from. How to read the labels.
Overview and location
Reported facility location HUC12 watershed Corroborated receiving water 2026 Integrated Report waterbodies nearby
Reported location Evidence: facility-reported
- Coordinates
- 34.11459, -117.98038
- Precision
- 5 decimal places
- Shared point
- 3 permits report this exact point
- Matches application record
- same
Facility location as reported by the discharger in SMARTS; not a discharge point or outfall.
- Facility address
- 1245 Arrow Hwy, Irwindale 91706
- Regional Water Board
- 4 — Los Angeles
HUC12 watershed Evidence: spatial
- Santa Anita Wash-Rio Hondo HUC12 180701050302
The facility's reported location lies within this HUC12 watershed (spatial derivation); it is not a discharge location.
Permits and applications Evidence: SMARTS record
Current permit record
- Permit type
- Industrial
- Application type
- Notice of Intent (WDID code I)
- Status
- Active
- Operator
- United Rock Products
- Primary industry (SIC)
- 1442-Construction Sand and Gravel
- Secondary SIC
- 3273-Ready-Mixed Concrete
- Tertiary SIC
- 2951-Asphalt Paving Mixtures and Blocks
- Application ID
- 188689
- NOI processed
- Mar 20, 1992
- Last certified
- Mar 13, 2024
- Facility size
- 150 Acres
- Impervious area
- 0 %
Retrieved from SMARTS Oct 20, 2026. Verify against SMARTS before relying on it.
Permit history
| Application | Type | Status | Processed | Terminated | Certified |
|---|---|---|---|---|---|
| 188689 | Industrial | Active | Mar 20, 1992 | — | Mar 13, 2024 |
Every storm water application SMARTS records for this WDID, newest first (1).
Receiving water
- Reported by the facility Evidence: facility-reported
- Sawpit Creek
- Discharges directly / indirectly
- N / Y (as answered in the permit application)
Evidence: identification corroborated Sawpit Creek CAR4053100020050119104537
Receiving water reported by facility — waterbody identification corroborated by geographic evidence.
Nearest distance from the reported facility location: 1.5 km. Method receiving_water/2.
2026 Integrated Report status Evidence: State-published
Sawpit Creek is on the 2026 Clean Water Act section 303(d) list (4 Appendix A decisions; category 5).
| Pollutant | Category | Listing decision | TMDL requirement | Decision ID |
|---|---|---|---|---|
| Bis(2ethylhexyl)phthalate (DEHP) | 5 | List on 303(d) list (TMDL required list) | 5A | 68164 |
| Chlordane | 5 | List on 303(d) list (TMDL required list) | 5A | 138798 |
| Indicator Bacteria | 5 | Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL) | 5B · Los Angeles River Pathogens (15) | 150333 |
| Lead | 5 | List on 303(d) list (TMDL required list) | 5A | 138802 |
Published by the State Water Resources Control Board (2026 California Integrated Report, Appendix A). Listing status is taken from Appendix A only. State Board adoption 2026-02-03; USEPA approval not confirmed. A listing describes the waterbody, not this facility. Waterbody profile.
Impaired waters and TMDLs
Two kinds of information, kept apart: 2026 Integrated Report waterbodies near the reported location (geographic proximity only), and TMDL records that SMARTS lists for this facility. Neither establishes where the facility discharges; see Receiving water for the facility's own statement.
Nearby waterbodies Evidence: geographic proximity
Spatial proximity only; discharge pathway not established. Being near a waterbody does not mean the facility discharges to it.
| Waterbody (2026 Integrated Report) | Distance | 2026 303(d) list | Appendix A decisions |
|---|---|---|---|
| San Gabriel River Reach 4 (Morris Dam to Ramona Blvd) CAR4053100020110720103544 | 894 m | not listed | 0 |
Waterbodies within 1.0 km of the reported facility location. Method proximity/1.
SMARTS TMDL records Evidence: SMARTS-reported
No TMDL records for this facility in the SMARTS TMDL export.
Reported monitoring results Evidence: facility-reported
Numeric Action Level (NAL) screening is being independently validated and is not shown. Nothing on this page states whether a result exceeded a NAL.
223 distinct measurements across 5 parameters, most recent sample Jan 29, 2021.
By reporting year
| Reporting year (July–June) | Distinct results | Parameters | With several versions | First sample | Last sample |
|---|---|---|---|---|---|
| 2020 | 15 | 5 | 0 | Dec 28, 2020 | Jan 29, 2021 |
| 2019 | 45 | 5 | 0 | Nov 20, 2019 | Apr 06, 2020 |
| 2018 | 70 | 5 | 0 | Dec 06, 2018 | Mar 06, 2019 |
| 2017 | 20 | 5 | 0 | Jan 09, 2018 | Mar 22, 2018 |
| 2016 | 35 | 5 | 0 | Dec 16, 2016 | Jan 19, 2017 |
| 2015 | 38 | 5 | 0 | Sep 15, 2015 | Mar 07, 2016 |
By parameter
| Parameter | Units | Measurements | Below detection | First sample | Last sample | Results |
|---|---|---|---|---|---|---|
| Iron, Total | mg/L | 45 | 0 | Sep 15, 2015 | Jan 29, 2021 | Results |
| Nitrite Plus Nitrate (as N) | mg/L | 45 | 2 | Sep 15, 2015 | Jan 29, 2021 | Results |
| Oil and Grease | mg/L | 45 | 33 | Sep 15, 2015 | Jan 29, 2021 | Results |
| pH | SU | 44 | 0 | Sep 15, 2015 | Jan 29, 2021 | Results |
| Total Suspended Solids (TSS) | mg/L | 44 | 0 | Sep 15, 2015 | Jan 29, 2021 | Results |
All results (223 distinct rows)
| Sample date | Parameter | Result | Units | Location type | Event | Method | Report | Versions |
|---|---|---|---|---|---|---|---|---|
| Jan 29, 2021 | Iron, Total | 3.15 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1145305 | |
| Jan 29, 2021 | Nitrite Plus Nitrate (as N) | DNQ .0327 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1145305 | |
| Jan 29, 2021 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1145305 | |
| Jan 29, 2021 | pH | 7.8 | SU | Effluent | Qualifying Storm Event | pH_Field | 1145305 | |
| Jan 29, 2021 | Total Suspended Solids (TSS) | 123 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1145305 | |
| Dec 28, 2020 | Iron, Total | 1.82 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1141605 | |
| Dec 28, 2020 | Iron, Total | 4.51 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1141605 | |
| Dec 28, 2020 | Nitrite Plus Nitrate (as N) | .311 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1141605 | |
| Dec 28, 2020 | Nitrite Plus Nitrate (as N) | .463 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1141605 | |
| Dec 28, 2020 | Oil and Grease | DNQ 2.21 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1141605 | |
| Dec 28, 2020 | Oil and Grease | DNQ 3.7 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1141605 | |
| Dec 28, 2020 | pH | 8.2 | SU | Effluent | Qualifying Storm Event | pH_Field | 1141605 | |
| Dec 28, 2020 | pH | 9.2 | SU | Effluent | Qualifying Storm Event | pH_Field | 1141605 | |
| Dec 28, 2020 | Total Suspended Solids (TSS) | 532 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1141605 | |
| Dec 28, 2020 | Total Suspended Solids (TSS) | 431 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1141605 | |
| Apr 06, 2020 | Iron, Total | 2.36 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1107459 | |
| Apr 06, 2020 | Iron, Total | .939 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1107459 | |
| Apr 06, 2020 | Iron, Total | 22.9 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1107459 | |
| Apr 06, 2020 | Nitrite Plus Nitrate (as N) | .0731 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1107459 | |
| Apr 06, 2020 | Nitrite Plus Nitrate (as N) | .163 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1107459 | |
| Apr 06, 2020 | Nitrite Plus Nitrate (as N) | .156 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1107459 | |
| Apr 06, 2020 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1107459 | |
| Apr 06, 2020 | Oil and Grease | DNQ 2.57 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1107459 | |
| Apr 06, 2020 | Oil and Grease | 9.16 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1107459 | |
| Apr 06, 2020 | pH | 7.1 | SU | Effluent | Qualifying Storm Event | pH_Field | 1107459 | |
| Apr 06, 2020 | pH | 7.1 | SU | Effluent | Qualifying Storm Event | pH_Field | 1107459 | |
| Apr 06, 2020 | pH | 8 | SU | Effluent | Qualifying Storm Event | pH_Field | 1107459 | |
| Apr 06, 2020 | Total Suspended Solids (TSS) | 11.4 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1107459 | |
| Apr 06, 2020 | Total Suspended Solids (TSS) | 13.5 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1107459 | |
| Apr 06, 2020 | Total Suspended Solids (TSS) | 307 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1107459 | |
| Mar 12, 2020 | Iron, Total | 4.18 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1107458 | |
| Mar 12, 2020 | Iron, Total | 10.5 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1107458 | |
| Mar 12, 2020 | Nitrite Plus Nitrate (as N) | .502 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1107458 | |
| Mar 12, 2020 | Nitrite Plus Nitrate (as N) | .413 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1107458 | |
| Mar 12, 2020 | Oil and Grease | DNQ 3.62 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1107458 | |
| Mar 12, 2020 | Oil and Grease | 6.88 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1107458 | |
| Mar 12, 2020 | pH | 7.8 | SU | Effluent | Qualifying Storm Event | pH_Field | 1107458 | |
| Mar 12, 2020 | pH | 8.2 | SU | Effluent | Qualifying Storm Event | pH_Field | 1107458 | |
| Mar 12, 2020 | Total Suspended Solids (TSS) | 292 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1107458 | |
| Mar 12, 2020 | Total Suspended Solids (TSS) | 118 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1107458 | |
| Dec 04, 2019 | Iron, Total | 3.02 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1100296 | |
| Dec 04, 2019 | Iron, Total | 13.8 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1100296 | |
| Dec 04, 2019 | Nitrite Plus Nitrate (as N) | .212 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1100296 | |
| Dec 04, 2019 | Nitrite Plus Nitrate (as N) | .172 | mg/L | Effluent | Qualifying Storm Event | A4500NE | 1100296 | |
| Dec 04, 2019 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1100296 | |
| Dec 04, 2019 | Oil and Grease | 13.2 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1100296 | |
| Dec 04, 2019 | pH | 7 | SU | Effluent | Qualifying Storm Event | pH_Paper | 1100296 | |
| Dec 04, 2019 | pH | 7 | SU | Effluent | Qualifying Storm Event | pH_Paper | 1100296 | |
| Dec 04, 2019 | Total Suspended Solids (TSS) | 209 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1100296 | |
| Dec 04, 2019 | Total Suspended Solids (TSS) | 231 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1100296 |
Results are shown exactly as reported by the discharger. Identical rows repeated in the State's export are shown once. Where the export contains different versions of the same sample and parameter, each version is listed and flagged. Details.
Compliance and enforcement records Evidence: SMARTS record
These are records as the State Water Board publishes them in SMARTS, with the source's own types and statuses. They are not a compliance determination or rating. A record listed here is not proof of a violation beyond what the source states, and the absence of records does not establish compliance.
| Record type | Records | As published | Dates | Retrieved | List |
|---|---|---|---|---|---|
| Violations | 7 | 7 Violation · 0 Potential (preliminary) · 0 Dismissed | Jul 02, 1993 – Dec 30, 2019 | Oct 21, 2026 | All violations |
| Enforcement actions | 3 | 3 issued · 0 draft · 0 withdrawn, rescinded or superseded | Dec 01, 1993 – Aug 14, 2020 | Oct 21, 2026 | All actions |
| Inspections | 2 | inspections, not findings | Oct 15, 2004 – Jun 20, 2024 | Oct 21, 2026 | All inspections |
| Annual reports | 11 | certified reports (contents not shown) | 2015 – 2025 | Oct 21, 2026 | All reports |
| Water-quality-based corrective action reports | 0 | reports, by parameter | — | Oct 21, 2026 |
Each record type is counted by its own SMARTS identifier. A violation and the enforcement action that cites it are two records in two lists; they are never added together.
Chronological record history (23 records, newest first)
| Date | Record | ID | Type or purpose | Status as published | Detail |
|---|---|---|---|---|---|
| Jul 06, 2026 | Annual reports | 1336442 | Annual report 2025 | — | |
| Jun 23, 2025 | Annual reports | 1295305 | Annual report 2024 | — | |
| Jul 15, 2024 | Annual reports | 1244440 | Annual report 2023 | — | |
| Jun 20, 2024 | Inspections | 2064744 | Complaint | Finalized | No Further Action |
| Jul 10, 2023 | Annual reports | 1190499 | Annual report 2022 | — | |
| Jul 11, 2022 | Annual reports | 1113985 | Annual report 2021 | — | |
| Jul 12, 2021 | Annual reports | 1070055 | Annual report 2020 | — | |
| Aug 14, 2020 | Enforcement actions | 437228 | NOV (Notice of Violation) | Historical | |
| Jul 10, 2020 | Annual reports | 987414 | Annual report 2019 | — | |
| Dec 30, 2019 | Violations | 873669 | Deficient Report | Violation | Report |
| Jun 28, 2019 | Annual reports | 955024 | Annual report 2018 | — | |
| Jul 09, 2018 | Annual reports | 940442 | Annual report 2017 | — | |
| Jul 11, 2017 | Annual reports | 879771 | Annual report 2016 | — | |
| Jul 08, 2016 | Annual reports | 846965 | Annual report 2015 | — | |
| Oct 15, 2004 | Inspections | 1735112 | B Type compliance | — | No Further Action |
| Dec 01, 1999 | Enforcement actions | 411456 | NOV (Notice of Violation) | Active | |
| Jul 02, 1999 | Violations | 850430 | Late Report | Violation | Report |
| Jul 02, 1998 | Violations | 850429 | Late Report | Violation | Report |
| Jul 02, 1997 | Violations | 850428 | Late Report | Violation | Report |
| Jul 02, 1996 | Violations | 850427 | Late Report | Violation | Report |
| Jul 02, 1995 | Violations | 850426 | Late Report | Violation | Report |
| Dec 01, 1993 | Enforcement actions | 411455 | 1st NNC - AR (First Notice of Non-Compliance (annual report)) | Active | |
| Jul 02, 1993 | Violations | 850425 | Late Report | Violation | Report |
Sources and provenance
| Information | Source | Retrieved or published |
|---|---|---|
| Permit, location, receiving-water text | SMARTS Industrial Application Specific Data | Oct 20, 2026 |
| Permit history | SMARTS Storm Water Applications | Oct 20, 2026 |
| Monitoring results | SMARTS Industrial Parameter Data | Oct 20, 2026 |
| 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 with methods facility_huc12/1, proximity/1, receiving_water/2, tmdl_reference/1, waterbody_huc12_ovl/1, waterbody_huc12_pub/1; proximity threshold 1.0 km.
How to read the evidence labels
- Evidence: SMARTS record Evidence: facility-reported Information as published in SMARTS or reported by the discharger.
- Evidence: identification corroborated The reported receiving-water name identifies one official waterbody and the facility's location is consistent with it. It does not establish a discharge pathway.
- Evidence: candidate, awaiting review Evidence: not confirmed The reported name could match one or more official waterbodies, but no identification has been confirmed; nothing is assigned without review.
- Evidence: spatial Evidence: geographic proximity Derived from the reported location only.
- Evidence: SMARTS-reported Source records whose links to official references are not yet reviewed.
- Evidence: unavailable The information could not be loaded or is not in the sources.
Records are shown as published and are not compliance determinations. How geographic context is derived.