NPDES Stormwater Permit

What is NPDES?

The National Pollutant Discharge Elimination System (NPDES) is a federal permit system that regulates the discharge of stormwater and wastewater to waters of the State.  Although it is a federal permit, the Department of Ecology (DOE) is the regulatory authority in Washington State.

The NPDES Phase II Municipal Stormwater Permit for Western Washington went into effect in February 2007. This permit authorizes the City of Redmond to discharge stormwater to waters of the State (i.e. Lake Sammamish) if it takes certain actions to prevent stormwater pollution. The full permit can be viewed at the DOE’s website: NPDES Phase II Municipal Stormwater Permit (link temporarily unavailable).

The permit requires the City to create and implement a Stormwater Management Program (SWMP). The SWMP outlines the City’s plan to develop and implement the following programs and processes: 

  • Public education and outreach 
  • Public involvement and participation 
  • Illicit discharge detection and elimination 
  • Controlling stormwater run-off from construction sites 
  • Operations and maintenance of stormwater facilities after construction

The documents listed below have been prepared in compliance with the NPDES permit. They are updated annually by the City and submitted to the DOE.

For questions or comments on how the City is meeting the NPDES Permit:

Peter Holte  -  425-556-2822