Puget Sound Olympia

Municipal Stormwater

Phase II Western Washington Municipal Stormwater Permit

The Phase II permit for western Washington covers at least 80 cities and portions of five counties with an effective date of September 1, 2012. The updated 2013-2018 permit became effective on August 1, 2013.

The EPA phase II regulations went into effect in early 2003 and apply to all regulated small municipal separate storm sewer systems. Ecology first issued the Western Washington Phase II permit in 2007 and modified it in 2009. Ecology reissued it unmodified on August 1, 2012 to be effective through July 31, 2013. At the same time, Ecology also reissued an updated 2013 to 2018 permit on August 1, 2012.

The files below are the permit as modified in December 2014 and went into effect as of January 16, 2015.

  • 2013-2018 Western Washington Phase II Municipal Stormwater Permit - Clean | Redline
  • Appendix 1. Minimum Technical Requirements or New Development and Redevelopment - Clean | Redline
  • Appendix 2. Total Maximum Daily Load Requirements - Clean | Redline
  • Appendix 3. Annual Report Questions for Cities, Towns and Counties - Clean | Redline
  • Appendix 4. Annual Report Questions for Secondary Permittees - Clean | Redline
  • Appendix 5. Notice of Intent for Coverage - Clean
  • Appendix 6. Street Waste Disposal - Clean
  • Appendix 7. Determining Construction Site Sediment Damage Potential - Clean
  • Appendix 8. Annual Report Questions for New Permittees - Clean | Redline
  • Appendix 9. Stormwater Discharge Monitoring - Clean | Redline

  • Response to Comments for Permit Modification Effective January 16, 2015

  • Errata issued February 2015

NEW 7/8/2016 2018 Western Washington Permit Reissuance

Regional Stormwater Monitoring Program

2014 Permit Modification

Western Washington Phase II Timelines Overview - for continuing permittees

New Permittees WWA Phase II Timelines Overview - for new permittees under the 2013-2018 permit

2012 Municipal Stormwater Permit Appeals

2012 Permits Reissuance Process

Annual Report Forms and Guidance

Permit History