The City of Seattle is in the process of updating Seattle’s Stormwater Code and Stormwater Manual as required by the Washington State Department of Ecology.
The second draft of the 2026 Stormwater Code and Manual documents will be available for public review and comment beginning January 7, 2026. The documents are available on SDCI’s Stormwater Code and Manual Update 2026 website. A public comment period will be open from January 7 though February 9.
A public meeting will be held on January 14, 2026, 1 PM to 3 PM. Please register to attend the meeting. The goal of the meeting is to share the changes made to the Manual to meet Ecology’s equivalency requirements and describe other key updates and changes in the second draft. The Department of Ecology requires the final Stormwater Code and Manual to take effect no later than July 1, 2026.
This information, along with information on past public meetings, is available on our Stormwater Code and Manual Update 2026 website.