Chelan County, WA Environmental Rules: Stormwater Management (2026)
Key Facts
- Governing section
- Chelan County Code Section 13.14.050
- Prohibited
- Any non-stormwater discharge into the MS4
- Development standard
- Stormwater Management Manual for Eastern Washington
- Repeat violation
- Misdemeanor, up to $1,000/day, 90 days jail
- Enforcing agencies
- Public Works and Community Development
Summary
Chelan County bans dumping anything but stormwater into its municipal separate storm sewer system in the unincorporated county. Section 13.14.050 prohibits illicit discharges and illicit connections to the storm drain system, carving out only specific exceptions like diverted stream flows and dechlorinated pool water. Chapter 13.16 separately adopts the Stormwater Management Manual for Eastern Washington to govern runoff from new development and land-disturbing activity, with Public Works and Community Development sharing enforcement.
No person shall throw, drain, or otherwise discharge, cause, or allow others under its control to throw, drain, or otherwise discharge into the MS4 any pollutants or waters containing any pollutants, other than stormwater. The commencement, conduct or continuance of any illicit discharge to the storm drain system is prohibited except as described as follows: ... Car washing is not prohibited, but provisions must be made to prohibit the wash water from entering the storm drain system.
Full Breakdown
14 of the Chelan County Code establishes the county's illicit discharge detection and elimination program for its municipal separate storm sewer system, or MS4. 050 prohibits discharging any pollutant other than stormwater into the MS4, and it prohibits illicit connections to the storm drain system outright, including connections made in the past regardless of whether they were lawful when installed. 1 ppm or less and swimming pool or spa water dechlorinated and temperature-controlled before release, while banning pool filter backwash outright. Car washing is not prohibited, but wash water may not reach the storm drain system.
16 adopts the Stormwater Management Manual for Eastern Washington by reference to control erosion and runoff from land-disturbing activity, tying the county's program to the Eastern Washington Phase II Municipal Stormwater Permit administered by the Washington State Department of Ecology. 14 at any time to sample discharges, install monitoring equipment, or verify compliance, and may seek a search warrant if access is refused. 06 in addition to the criminal penalties specific to repeat stormwater violations.
Violations & Fines
A first stormwater discharge or illicit connection violation is handled under Chapter 16.06's notice and order process. Anyone who violates Chapter 13.14 two or more times is guilty of a misdemeanor under Section 13.14.090, punishable by a fine up to $1,000 per violation per day and up to 90 days in jail per violation per day, with each day of continuing violation a separate offense. The county may also recover abatement costs, attorneys fees and court costs, and unpaid charges become a lien after 90 days.
Frequently Asked Questions
What can and cannot be discharged into Chelan County's storm drains?
What stormwater standards apply to new development in Chelan County?
What is the penalty for repeatedly violating Chelan County's stormwater rules?
Sources & Official References
Other rules in Chelan County
Compare Chelan County to another location·View the Washington environmental rules overview
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