Industrial stormwater facility
4 19I010791 · Notice of Intent · Monrovia, Los Angeles
Official
Hydrologic
Official facility coordinate plotted against the official 2026 impaired-water geometry.
303(d) context
Grouped by derived geographic association class.
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (4) Bis(2ethylhexyl)phthalate (DEHP), Chlordane, Indicator Bacteria, Lead
Lake & Reservoir · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (6) Chlordane (tissue), DDT (tissue), Mercury, Odor, Organic Enrichment/Low Dissolved Oxygen, Trash
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (2) Indicator Bacteria, Lead
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (5) Copper, Indicator Bacteria, Iron, Oxygen, Dissolved, Zinc
River & Stream · Integrated Report category 4a · TMDL approved by USEPA
Listed pollutants / stressors (1) Lead
Associations are calculated from official facility coordinates, USGS HUC12 boundaries, and official 2026 impaired-water geometry. They do not establish a discharge connection or causation.
Numeric effluent limits and action levels stated by the Water Board for this permit, with the receiving water named in the TMDL.
Receiving water named in TMDL Los Angeles River and Los Angeles River Tributaries
| Parameter | Limit type | Period | Basis | Limit | Due date | Reported results for parameter |
|---|---|---|---|---|---|---|
| Copper, TotalVocabulary match: Copper (narrower) | NEL | FINAL | INSTANTANEOUS | .06749 mg/L | 2020-07-01 | 156 results · latest 2026-02-16 |
| Lead, TotalVocabulary match: Lead (narrower) | NEL | FINAL | INSTANTANEOUS | .094 mg/L | 2020-07-01 | 172 results · latest 2026-02-16 |
| Zinc, TotalVocabulary match: Zinc (narrower) | NEL | FINAL | INSTANTANEOUS | .159 mg/L | 2020-07-01 | 132 results · latest 2026-02-16 |
Limit values, limit periods, parameters, TMDL names and receiving-water names are reproduced exactly as stated by the Water Board in SMARTS. California Stormwater Intelligence does not compare reported monitoring results to these limits and makes no exceedance, violation or compliance determination. Where a stated receiving-water name is linked to a 2026 303(d) waterbody, that link is a derived exact-name match, not a Water Board determination.
Official monitoring
Self-reported industrial stormwater sampling results as submitted by the discharger to SMARTS.
Loading reported results…
| Sample date | Location | Parameter | Result | Units | Event |
|---|---|---|---|---|---|
| 2026-02-16 | OF-001 (Outfall 1) | Aluminum | 1.88 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Aluminum | 1.88 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Aluminum | 1.88 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Aluminum | 1.88 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Copper | .0473 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Copper | .0473 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Copper | .0473 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Copper | .0473 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Iron | 2.85 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Iron | 2.85 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Iron | 2.85 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Iron | 2.85 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Lead | .0188 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Lead | .0188 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Lead | .0188 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Lead | .0188 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Oil and Grease | 5.37 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Oil and Grease | 5.37 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Oil and Grease | 5.37 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Oil and Grease | 5.37 | mg/L | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | pH | 7.5 | SU | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | pH | 7.5 | SU | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | pH | 7.5 | SU | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | pH | 7.5 | SU | Qualifying Storm Event |
| 2026-02-16 | OF-001 (Outfall 1) | Total Suspended Solids (TSS) | 55.8 | mg/L | Qualifying Storm Event |
Monitoring rows are official self-reported SMARTS submissions, joined to this facility by WDID. California Stormwater Intelligence does not restate, correct, average or evaluate reported values, and no benchmark comparison or violation determination is made.
YDOS-derived
Reported SMARTS analytical results compared against the Numeric Action Levels of the Industrial General Permit version in effect for each reporting year (July 1 – June 30).
| Parameter | NAL type | Calculated value | NAL | Result | Samples used | Method |
|---|---|---|---|---|---|---|
Aluminum, Total aluminum_total | Annual | 1.353 mg/L | 0.75 mg/L | Above NALAnnual average of 8 eligible result(s) compared with the annual NAL.1.8× threshold | 8 eligible24 excluded | arithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported) |
Copper, Total copper_total | Annual | 0.053 mg/L | 0.033 mg/L | Above NALAnnual average of 8 eligible result(s) compared with the annual NAL.1.61× threshold | 8 eligible24 excluded | arithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported) |
Iron, Total iron_total | Annual | 2.065 mg/L | 1 mg/L | Above NALAnnual average of 8 eligible result(s) compared with the annual NAL.2.06× threshold | 8 eligible24 excluded | arithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported) |
Lead, Total lead_total | Annual | 0.014 mg/L | 0.262 mg/L | At or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0.05× threshold | 8 eligible24 excluded | arithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported) |
Oil and Grease oil_grease | Instantaneous maximum | —0 samples above | 25 mg/L | At or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL. | 8 eligible24 excluded | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
pH ph | Instantaneous maximum | —0 samples above | 6 – 9 pH units | Within NAL rangeNo eligible result in this reporting year was outside the instantaneous maximum NAL. | 8 eligible24 excluded | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
Total Suspended Solids (TSS) tss | Instantaneous maximum | —0 samples above | 400 mg/L | At or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL. | 8 eligible24 excluded | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
Zinc, Total zinc_total | Annual | 0.144 mg/L | 0.26 mg/L | At or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0.56× threshold | 8 eligible24 excluded | arithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported) |
YDOS-derived overlap
Parameters where this facility has an NAL exceedance in at least one reporting year and the geographically associated waterbody carries a 303(d) listing for the same pollutant.
CopperMonitoringAbove NAL303(d) impairmentRio Hondo Reach 3 (above Spreading Grounds)
11 reporting years above the annual NAL, most recently RY 2025 · 1 303(d) listing · 1 stated TMDL requirement · association: derived nearby in watershed (high confidence)
IronMonitoringAbove NAL303(d) impairmentRio Hondo Reach 3 (above Spreading Grounds)
9 reporting years above the annual NAL, most recently RY 2025 · 1 303(d) listing · association: derived nearby in watershed (high confidence)
ZincMonitoringAbove NAL303(d) impairmentRio Hondo Reach 3 (above Spreading Grounds)
2 reporting years above the annual NAL, most recently RY 2023 · 1 303(d) listing · 1 stated TMDL requirement · association: derived nearby in watershed (high confidence)
Overlap is informational co-occurrence between a derived NAL comparison and an official 303(d) listing. It is not evidence that this facility caused or contributed to the impairment.
An NAL exceedance is a permit-defined condition that triggers Exceedance Response Actions under the Industrial General Permit. It is not a violation, an enforcement action, or a Water Board compliance determination. Annual values use the arithmetic average of eligible results with non-detects treated as zero; instantaneous maximum NALs (total suspended solids, oil and grease, pH) are exceeded when two or more eligible results in a reporting year fall outside the level. Rules transcribed from 2014-0057-DWQ as amended by 2015-0122-DWQ ↗ (effective 2015-07-01, superseded 2020-06-30); 2014-0057-DWQ as amended by 2018-0028-DWQ ↗ (effective 2020-07-01).
Provenance