The City of Seattle is in the process of updating the Stormwater Code and the Seattle Stormwater Manual.
The first draft of the updated Code and Stormwater Manual, that addresses equivalency with the State of Washington Department of Ecology (Ecology) rules and permits, is nearing completion. We will share it with you July 7. A second draft will be shared with you in January 2026 after we address your comments and Ecology’s comments. The second draft will also address other items that are not related to Ecology requirements.
Get Involved
We’d like to invite you to get involved by providing comments during the upcoming public review periods. There will be 2 public comment periods prior to submitting the final drafts to the City Council, the Mayor’s Office, and our Department Directors.
The first public comment period is coming up and will be from July 7-August 5, with a public meeting on July 15. The second will be in the winter of 2026.
Register here to attend the virtual public meeting on July 15 from 1:00 – 3:00 p.m. It will be about the changes in the first draft of the Stormwater Code and Manual.
For additional information about the public comment periods, how to make comments, and how to attend the public meetings, see the Get Involved page on our Stormwater Code Update website.
Also, sign up for the SDCI Stormwater Code Updates Listserv if you want to get email updates on project milestones, available documents, and upcoming public meetings.
Background
Ecology requires that we update our current codes with additional stormwater control regulations as a condition of our Ecology Phase 1 Municipal Stormwater permit (Ecology Permit). The Ecology permit enforces the requirements of the National Pollutant Discharge Elimination System (NPDES) permit. We are revising our existing Stormwater Code (SMC 22.800-22.808), Seattle’s Stormwater Manual (Directors’ Rule 10-2021), and other associated Director’s Rules to meet these requirements. These new rules will replace the current code and Directors’ Rules which are administered jointly by the Seattle Department of Construction and Inspections (SDCI) and Seattle Public Utilities (SPU).
These new rules will replace the current code and Directors’ Rules which are administered jointly by SDCI and SPU.
For more information visit our Stormwater Code Update website.