Contra Costa County, CA Environmental Rules: Stormwater Management (2026)
Key Facts
- Governing law
- Ordinance Code Division 1014
- Illicit discharge
- Any non-stormwater release is banned
- Plan trigger
- 5,000 sq ft impervious surface (since 7/1/23)
- Enforcement
- Misdemeanor or infraction
- Civil remedy
- Injunction, cost recovery, damages
- Administered by
- Director of Public Works
Summary
In unincorporated Contra Costa County, releasing anything other than stormwater into a gutter, storm drain, creek, or ditch is banned outright under the county's Division 1014 stormwater ordinance. New projects that create 5,000 square feet or more of impervious surface must also file a county-approved stormwater control plan before permits will issue.
(a)The release of illicit discharges to the county stormwater system is prohibited. ... Notwithstanding any other provision of this code, any person, firm, partnership, corporation or public agency that violates any provision of this division, or fails to comply with any of the mandatory requirements of this division, is guilty of a misdemeanor, unless, in the discretion of the public works director (as provided in this code) or the district attorney, it is charged and prosecuted as an infraction.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Ordinance Code: Supplement 103).
Full Breakdown
004 as any discharge to the county's stormwater system that is not composed entirely of stormwater, unless it complies with an NPDES permit. 006(b)-(c) cover things like uncontaminated groundwater, air conditioning condensate, individual residential car washing, and dechlorinated pool or spa water. 004(c)). Applications are not deemed complete until that plan is reviewed and approved, and a stormwater facilities operation and maintenance plan must be submitted before the county will issue a certificate of occupancy or final inspection. 014). 012).
Violations & Fines
A violation of Division 1014 is a misdemeanor unless the Public Works Director or the district attorney charges it as an infraction (Section 1014-6.002), with punishment set under Chapter 14-8. The county can also sue civilly for a temporary restraining order or injunction, recover investigation and cleanup costs, and collect compensatory damages for water quality or wildlife loss (Section 1014-6.014). Any violating condition is separately declared a public nuisance abatable under Chapter 14-6, and each day a violation continues is treated as a separate offense under Section 1014-6.006.
Frequently Asked Questions
What counts as an illegal discharge into Contra Costa County's storm drains?
Does building a new home in unincorporated Contra Costa County require a stormwater plan?
Can I still wash my car or water my lawn at home?
What happens if I'm caught violating the stormwater ordinance?
Sources & Official References
Other rules in Contra Costa County
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