WSR 16-11-060
[Filed May 13, 2016, 1:57 p.m.]
Purpose of the Phase I Municipal Stormwater General Permit: Federal and state water quality laws require a permit for the discharge of stormwater (see Federal Water Pollution Control Act Title 22 United States Code, Section 1251 et seq., state Water Pollution Control Act chapter 90.48 RCW and Washington waste discharge general permit regulation WAC 173-226-130). The Phase I municipal stormwater general permit (permit) regulates the discharges from storm sewer systems owned or operated by Clark, King, Pierce and Snohomish counties; the cities of Seattle and Tacoma; and public entities located in these cities and counties. The permit requires these municipalities and secondary permittees to protect surface water and groundwater quality by developing and implementing a stormwater management program to control stormwater runoff into and from their storm sewer systems.
Proposed Modifications: The department of ecology (ecology) issued a modified draft Phase I municipal stormwater general permit for public review and comment on May 18, 2016. The permit went into effect on August 1, 2013; an earlier modification went into effect on January 16, 2015.
Ecology is modifying the permit a second time. One of the permit requirements is for Phase I municipalities to adopt a stormwater program that will provide equal or similar protection of receiving waters and pollutant control as compared to Appendix 1 of the permit. This modification will incorporate, in Appendix 10 of the permit, ecology's determination of equivalency for these stormwater programs.
The modification also incorporates a new appendix, Appendix 13, which describes and requires an adaptive management plan for pollutants that discharge from the city of Seattle's municipal separate storm sewer system outfalls to the Lower Duwamish Waterway.
Applying for a Permit: Facilities covered under the existing municipal stormwater general permits will continue to be covered under the modified permits. Areas covered by the Phase I stormwater permit are shown here
Requesting Copies of the Proposed Permit Modifications: Beginning May 18, 2016, you may download copies of the draft permit and supporting documents online at
Ecology Contact: For questions concerning the permit modification contact Abbey Stockwell, Washington State Department of Ecology, P.O. Box 47600, Olympia, WA 98504-7600, phone (360) 407-7221, e-mail
Submitting Written and Oral Comments: Ecology will accept written and oral comments on the modified draft permit and supporting documents until 11:59 p.m., June 30, 2016. Ecology prefers comments to be submitted by e-mail Comments should reference the specific text when possible.
Submit written, hard copy comments to Municipal Permit Comments, Washington State Department of Ecology, P.O. Box 47600, Olympia, WA 98504-7600.
Written comments must be postmarked or e-mailed no later than 11:59 p.m., June 30, 2016.
Public Hearings and Workshops: Ecology will hold two workshops and public hearings on the modification. At the workshop, ecology will explain the modification and answer questions. A hearing will immediately follow each workshop. The hearings will provide the opportunity for people to give formal oral testimony and comment on the proposed modified draft permit.
Public Workshops and Hearings: On June 23, 2016, at 9:00 a.m., in person at SSC Georgetown Campus, 6737 Corson Avenue South, Gene J. Colin Educational Hall, Room 111, Seattle, WA 98108 (parking is available for $3.00 a day); and on June 29, 2016, at 2:30 p.m., via webinar and in person at the Washington State Department of Ecology, 300 Desmond Drive, Lacey, WA 98503-1274 (for more details about the webinar, please visit
Issuing the Final Modified Permit: After ecology receives and considers all public comments, we will issue the final modified permit and a response to comments. Ecology expects to issue the final modified permit in July 2016. The permit will be effective thirty days later. If ecology receives significant comments on the new Appendix 13, we may delay including Appendix 13 in the initial modification until comments are addressed. We would then issue another modification and supplemental response to comments, relying on the single draft comment period.