NPDES Stormwater Permit

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

National Pollutant Discharge Elimination System (NPDES)

The NPDES permit requires the City to take numerous actions to reduce the amount of polluted surface and stormwater runoff flowing into our creeks, streams, rivers, and groundwater. This Permit is issued to the City by the Washington State Department of Ecology and satisfies a mandate within the Federal Water Pollution Control Act of 1948. Due to growing public awareness and concern it was amended in 1972 and is now commonly known as the Clean Water Act (CWA). 

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

Learn More! Water Cycle Glossary of Terms

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Contact Us: 

Public Works Office
14525 Main St. NE
P.O. Box 1300
Duvall, WA 98019
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Ph: 425.788.3434
Fx: 425.788.0311

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Ph: 425.419.3748 (Please note this number does not receive text messages)

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