Industrial stormwater facility
WDID 4 19I022488 · Notice of Intent · Castaic, Los Angeles
SIC 4953 · Refuse Systems · Regional Board 4 - Los Angeles Region
Hydrologic
Official facility coordinate plotted against the associated Final 2026 Integrated Report impaired-water geometry.
Geometry shown is limited to waterbodies geographically associated with this facility. Geographic association does not establish a discharge connection, receiving-water connectivity, or causation.
Intelligence summary
What is available for this facility across the connected datasets.
Official
303(d) context
Grouped by derived geographic association class.
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (13) Aluminum, Benthic Community Effects, Bifenthrin, Chloride, Chlorine, Cyanide +7 more
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (1) Manganese
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (4) Benthic Community Effects, Chloride, Chlorpyrifos, Toxicity
River & Stream · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (15) Bifenthrin, Chlordane, Chloride, Cypermethrin, DDD (Dichlorodiphenyldichloroethane), DDE (Dichlorodiphenyldichloroethylene) +9 more
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 Santa Clara River Reaches 3, 4, 5, 6, and 7
| Parameter | Limit type | Period | Basis | Limit | Due date | Reported results for parameter |
|---|---|---|---|---|---|---|
| E.coliVocabulary match: Escherichia coli (E. coli) (alias) | TMDL NAL | FINAL | INSTANTANEOUS | 235 MPN/100 mL | 2020-07-01 | 17 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 | South | Chloride | 42 | mg/L | Qualifying Storm Event |
| 2026-02-16 | South | Escherichia coli (E. coli) | 240 | MPN/100 mL | Qualifying Storm Event |
| 2026-02-16 | South | Iron | 5.7 | mg/L | Qualifying Storm Event |
| 2026-02-16 | South | Oil and Grease | ND —(non-detect / est.) | mg/L | Qualifying Storm Event |
| 2026-02-16 | South | pH | 8.74 | SU | Qualifying Storm Event |
| 2026-02-16 | South | Total Coliform | > 1600(non-detect / est.) | MPN/100 mL | Qualifying Storm Event |
| 2026-02-16 | South | Total Suspended Solids (TSS) | 280 | mg/L | Qualifying Storm Event |
| 2026-02-16 | South | Zinc | .031 | mg/L | Qualifying Storm Event |
| 2026-02-11 | South | Chloride | 45 | mg/L | Qualifying Storm Event |
| 2026-02-11 | South | Escherichia coli (E. coli) | 130 | MPN/100 mL | Qualifying Storm Event |
| 2026-02-11 | South | Iron | 1.5 | mg/L | Qualifying Storm Event |
| 2026-02-11 | South | Oil and Grease | ND —(non-detect / est.) | mg/L | Qualifying Storm Event |
| 2026-02-11 | South | pH | 8.69 | SU | Qualifying Storm Event |
| 2026-02-11 | South | Total Coliform | 1600 | MPN/100 mL | Qualifying Storm Event |
| 2026-02-11 | South | Total Suspended Solids (TSS) | 70 | mg/L | Qualifying Storm Event |
| 2026-02-11 | South | Zinc | .015 | mg/L | Qualifying Storm Event |
| 2026-01-01 | South | BOD, Biochemical oxygen demand | 5.2 | mg/L | Qualifying Storm Event |
| 2026-01-01 | South | Chloride | 39 | mg/L | Qualifying Storm Event |
| 2026-01-01 | South | Escherichia coli (E. coli) | 240 | MPN/100 mL | Qualifying Storm Event |
| 2026-01-01 | South | Iron | 10 | mg/L | Qualifying Storm Event |
| 2026-01-01 | South | Oil and Grease | ND —(non-detect / est.) | mg/L | Qualifying Storm Event |
| 2026-01-01 | South | pH | 8.21 | SU | Qualifying Storm Event |
| 2026-01-01 | South | Total Coliform | > 1600(non-detect / est.) | MPN/100 mL | Qualifying Storm Event |
| 2026-01-01 | South | Total Suspended Solids (TSS) | 250 | mg/L | Qualifying Storm Event |
| 2025-12-24 | South | BOD, Biochemical oxygen demand | 8.8 | 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 |
|---|---|---|---|---|---|---|
Biochemical Oxygen Demand (BOD) (5-day @ 20 Deg. C) bod | Annual | 11.25 mg/L | 30 mg/L | At or below NALAnnual average of 4 eligible result(s) compared with the annual NAL.0.38× threshold | 4 eligible | 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 | 11.583 mg/L | 1 mg/L | Above NALAnnual average of 6 eligible result(s) compared with the annual NAL.11.58× threshold | 6 eligible | 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. | 6 eligible6 non-detect as zero | 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. | 6 eligible | 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 | —1 sample above | 400 mg/L | At or below NALOne eligible result in this reporting year was outside the instantaneous maximum NAL. The Order states the condition as two or more results in one reporting year. | 6 eligible | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
Zinc, Total zinc_total | Annual | 0.023 mg/L | 0.26 mg/L | At or below NALAnnual average of 2 eligible result(s) compared with the annual NAL.0.09× threshold | 2 eligible | 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.
IronMonitoringAbove NAL303(d) impairmentSanta Clara River Reach 5 (Blue Cut gaging station to West Pier Hwy 99 Bridge) (was named Santa Clara River Reach 7 on 2002 303(d) list)
8 reporting years above the annual NAL, most recently RY 2025 · 1 303(d) listing · 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).
Documents
Attachment inventory recorded in the State Water Board SMARTS public attachment workflow for this permit.
No document inventory has been indexed for this permit yet. The statewide document index is being built out; coverage is reported on the data-freshness panel.
Attachments for this permit remain viewable in the source system. Open the SMARTS public workflow ↗
Enforcement
Enforcement actions as recorded by the State Water Board for this permit, in the source system's own terminology.
Structured enforcement records are not yet connected for this site. The absence of a record is not a finding about this facility.
Reporting
Annual report and Exceedance Response Action information as stated by the source system, distinguished from what is inferred from document metadata.
Structured reporting and ERA records are not yet connected for this site.
Recent activity
New or changed source records this platform detected for this permit, newest first.
No source change has been detected for this permit yet. Change detection begins from the date each dataset was first indexed.
Provenance