Stormwater Management Program

The Public Works Department has prepared a Stormwater Management Program (SWMP) as required by the National Pollutant Discharge Elimination System (NPDES) Phase II Municipal Permit (the Permit) issued by the Washington State Department of Ecology (Ecology). The permit requires the City to submit Annual Reports on its stormwater activities and annual updates to its SWMP Plan for future stormwater activities. These can be found at the links at the bottom of the page.

Ecology Manual


To mitigate for impacts associated with stormwater runoff, the city requires that stormwater management practices be designed, constructed, operated and maintained in accordance with the Stormwater Management Manual for Western Washington (SWMMWW) prepared by Ecology. The current SWMMWW can be accessed from the Ecology website.

Green Building & LID


In addition to the Ecology Manual, surface water impacts can be mitigated through green building practices or Low Impact Development (LID) practices. Green building and LID practices are not just for new construction. These practices can also be considered for redevelopment projects. The city has some information regarding green building practices available at the permit counter. Additional information can be found from the U.S. Green Building Council.

Protecting Water Quality


For sites with existing development that have a stormwater permit, maintaining the stormwater management facilities and conveyance system in accordance with the permit requirements and the Ecology Manual represent actions that can be taken to protect water resources from stormwater runoff impacts. For sites that were developed prior to stormwater permitting requirements, actions that can be taken to protect water resources from stormwater runoff impacts include: 

  • Good housekeeping and source control Best Management Practices (BMPs) presented in Volume IV of Ecology's Manual
  • Implementing appropriate actions based on the Washington Waters Ours to Protect campaign.
  • Natural Yard Care. Information can be found from the City of Seattle website.
  • If you are aware of hazardous spills (illicit discharges) into a stormwater system, ditch or other waterway, please contact:
    • Public Works Department: Monday - Friday, 8 a.m. - 4:30 p.m. at 360-825-3593
    • Enumclaw Police Department after hours and on holidays at 360-825-3505
  • Other contact numbers and for spills outside of City limits:
    • Washington Emergency Management Division: 800-258-5990 or 800-OILS-911
    • Washington State Department of Ecology Northwest Region, 425-649-7000
    • National Response Center: 800-424-8802

Stormwater Management Program Reports


The City will continue to provide information to residents and businesses regarding stormwater management. In addition, City staff will review the effectiveness of public outreach efforts based on the Stormwater Management Program.

The Stormwater Management Program Plan is updated at least annually.  Click on the link below to view the 2016 Stormwater Management Program Plan.       
     
      2016 Stormwater Management Program Plan
     2015 Annual Report