Construction Stormwater General Permit
Coronavirus (COVID-19) status update
Signed original documents must still be mailed to us, but to expedite application processing please scan (photo ok) all forms (except ESAFs) and email them to email@example.com. Please scan and email Electronic Signature Agreement Forms (ESAFs) to firstname.lastname@example.org.
We are still continuing to process electronic permit related documents, but we may have extended turnaround times. Also, at this time, we are unable to print documents and may have to provide printed items at a later date. In lieu of printed documents we are emailing coverage letters and other documents to the permittee on file.
If you have any questions, our preference is to contact us via the email addresses below.
Stormwater runoff from construction sites can carry muddy water, debris, and chemicals into local waterways. Sediments, chemicals, and debris can harm aquatic life and reduce water quality.
We require regulated construction sites to get coverage under the Construction Stormwater General Permit (CSWGP). Following the requirements in this permit helps control and reduce water pollution. If water on your construction site is contaminated see this guidance for contaminated water on construction sites.
Operators of regulated construction sites are required to:
- Develop stormwater pollution prevention plans.
- Implement sediment, erosion, and pollution prevention control measures.
- Obtain coverage under this permit.
The current modified permit went into effect May 5, 2017, and expires Dec. 31, 2020.
To receive updates about this permit, sign up for our listserv
Current permit and recent modification
The current permit expires on December 31, 2020. The permit reissuance process includes informal listening sessions, a formal public comment period on the draft permit, and formal public meetings and hearings. We plan to make a permit reissuance decision at the end of this process in November of 2020.
Changes to the permit that are being considered include:
- Requirement to include a site map at the time of application
- Update of records retention requirement from three (3) to five (5) years
- Clarifying and streamlining certain sections related to inspections and monitoring
- Other issues identified through informal listening sessions and public input
Spring 2020: Informal Listening Sessions
Summer 2020: Formal public comment period on the draft permit
Fall 2020: Decision on reissuance
December 2020: Current permit expires
Listening Sessions Occurred:
Applications and forms
I've got permit coverage. Now what?
Check out our eCoverage packet for more information about your requirements.
Need help implementing the permit?
What do I do with contaminated water?
See contaminated water on construction sites for guidance.
Not finding what you're looking for?
See our regional contacts
page to help find a person to answer to your questions.
For Permittees in the following cities and counties:
City of Seattle, Skagit, or Whatcom County
Clark, Cowlitz, Grays Harbor, Jefferson, Lewis, Mason, Pacific, Skamania, Thurston or Wahkiakum County
Benton, Island, King County (exception for the City of Seattle), Kittitas, Klickitat County, San Juan, or Yakima County
Adams, Asotin, Chelan, Clallam, Columbia, Douglas, Ferry, Franklin, Garfield, Grant, Kitsap, Lincoln, Okanogan, Pend Oreille, Snohomish, Spokane, Stevens, Walla Walla, or Whitman County
Construction Stormwater General Permit Questions:
General Permit Writer