NPDES Stormwater Permit

  1. NPDES Stormwater Permit
  2. Annual Reports
  3. Stormwater Management Plan
  4. Public Education
  5. Stewardship
  6. Stencil a Storm Drain
  7. Adopt a Drain
  8. Illicit Discharges and Spills
  9. Private Storm Drainage Maintenance
  10. Low Impact Development (LID)

National Pollutant Discharge Elimination System (NPDES)
The National Pollutant Discharge Elimination System (NPDES) permit requires the City to take numerous actions to reduce the amount of polluted stormwater runoff flowing into our rivers, streams, and groundwater. This permit satisfies a mandate within the Federal Clean Water Act, and is issued to the City but the Washington State Department of Ecology. 

This permit requires the city to:

  • Provide Outreach and Education: work with people and businesses to promote daily activities that reduce stormwater pollution.
  • Inform and involve the public: give people the opportunity to weigh-in on how we meet permit requirements.
  • Respond to spills and seek out cross-connection pipes: this activity is called an "illicit discharge detection and elimination program (Spill Response).
  • Review development projects: ensure stormwater facilities are built to City standards, and that construction activities don't pollute stormwater.
  • Inspect and maintain public facilities: inspect and clean infrastructure, and make repairs if necessary.
  • Inspect and ensure private facilities are maintained: inspect private facilities and ensure property owners maintain and make repairs if necessary.

NPDES Municipal Stormwater Permit

Spill Hotline_2021

Contact Us:

Public Works Director email 

Public Works Office

14525 Main St. NE
P.O. Box 1300
Duvall, WA 98019
Directions (PDF)

Ph: 425.788.3434
Fx: 425.788.0311

After Hours Public Works Emergency
Ph: 425.419.3748 (Please note this number does not receive text messages)

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