Imperial County, CA Environmental Rules: Stormwater Management (2026)
Key Facts
- Authority
- NPDES Permit No. CAS000004
- Core rule
- No non-stormwater discharges
- Exemptions
- Water line flushing, AC condensate, etc.
- Ag exemption
- Agricultural activities exempted
Summary
Imperial County bans discharging non-stormwater or pollutant-laden runoff into the county's stormwater conveyance system under its NPDES-driven Stormwater Control Ordinance, with limited listed exemptions.
Except as provided in Section 93102.01, no person shall discharge, facilitate, cause, permit, or allow to be discharged to the stormwater conveyance system, either directly or indirectly, any of the following: A. Any non-stormwater, except in compliance with the requirements of this division; B. Any stormwater that may cause or threaten to cause a condition of pollution or nuisance, as defined in California Water Code section 13050; ... D. Stormwater containing hazardous substances.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 62 - 9-25).
Full Breakdown
Adopted to meet the county's state Small MS4 NPDES permit (Order No. 2013-0001-DWQ), the Stormwater Control Ordinance bars discharging non-stormwater, pollutants, or runoff that threatens water quality into the county's storm drains, streets, gutters and channels. A narrow list of exemptions applies -- water line flushing, air conditioning condensate, dechlorinated pool water, diverted springs and similar flows -- and agricultural activity is exempted outright. Illicit connections to the system are separately and flatly prohibited, and a responsible party who causes a discharge must immediately contain it and notify the county within 24 hours.
Violations & Fines
An illicit discharge or connection to the county's storm drain system is unlawful; the enforcement agency can order cease-and-desist, require cleanup within 72 hours to 30 days, and pursue Title 9, Division 13 enforcement remedies.
Frequently Asked Questions
Can I hose pollutants into a street drain in unincorporated Imperial County?
Does the stormwater ordinance cover farm operations?
Sources & Official References
Other rules in Imperial County
California rules heatmap·Compare Imperial County to another location·View the California environmental rules overview
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