Jul. 3, 2019 Municipal Stormwater General Permits and Western Manual

Updates Issued

On July 1, 2019, Ecology reissued the Municipal Stormwater General Permits. These permits require municipalities to manage stormwater and control runoff into and from their municipal separate storm sewer system to protect water quality in Washington. The permits become effective on August 1, 2019, and expire on July 31, 2024.

Copies of the permits

You can find the final permits, Fact Sheet (including the Response to Comments), and supporting documents on our website at or specifically at the links below.

· Phase I

· Western Washington Phase II

· Eastern Washington Phase II

You may also request copies from Dena Jaskar, at 360-407-6401, or by email at

Updates to the Western Stormwater Manual

We are also releasing the revised Stormwater Management Manual for Western Washington. The revised manual for Eastern Washington was released earlier this year. Both manuals are available on our stormwater manuals webpage. The manuals provide technical guidance for permit implementation.

We worked with permittees and interested parties for multiple years leading up to the reissuance

We ran an inclusive stakeholder process to ensure the reissued permits and manual meet the Clean Water Act and provide effective guidance for permittees. The last comment period was held August 15 to November 14, 2018. We accepted oral comments at seven public hearings preceded by workshops held across the state. The comments and our Response to Comments are included as an appendix to the Fact Sheet.

Your Right to Appeal

You have a right to appeal the final general permit and the general permit coverage for a specific facility to the Pollution Control Hearings Board (PCHB). The appeal process is governed by Chapter 43.21B RCW and Chapter 371-08 WAC.


Abbey Stockwell – Senior Municipal Stormwater Planner


Phone: (360) 407-6127