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Green-Duwamish-Watershed-StrategyKing County and the City of Seattle have teamed up to improve conditions throughout the watershed surrounding the Green and Duwamish rivers, stretching 93 miles from the Cascades to Elliott Bay.

  • Our goal is to coordinate the work already being done by local, state, and federal agencies to manage habitat restoration, salmon recovery, flood control, public health, economic development, and more.
  • This includes cleanup of the 5-mile stretch of the Lower Duwamish that is registered as a Superfund site.

The strategy also addresses the need to reduce pollution that occurs upstream, such as stormwater runoff that brings motor oil, pesticides, and other contaminates into the watershed and, ultimately, into the Lower Duwamish, Elliott Bay, and Puget Sound.

Read the Exec's announcement of the Green/Duwamish Watershed Strategy, and learn more about the EPA's final Lower Duwamish Waterway Superfund cleanup plan. The EPA's decision complements the Executive's effort to coordinate work being done across the 500-square-mile watershed.

Get detailed updates on recent events, strategy planning and stakeholder engagement at Our Green Duwamish (external site).

How it works

The Green/Duwamish Watershed isn't a series of isolated partsriver, uplands, habitatsit's one connected whole. Our approach to protecting the entire Watershed should be just as connected.

  • Instead of tackling one issue at a time, typically in response to a regulatory mandate or natural disaster, we will use the best available science and emerging technologies to link projects to outcomes for cleaner air, land, and water.
  • In addition to cleaning up historic contamination in the Lower Duwamish, we will address pollution at its sourceall the way upstream into the Cascades, to ensure long-term results.
  • It's not just the single polluter with a big pipe emptying into the rivermuch of that has already been taken care of. The threat today comes from our homes, lawns, and cars. Stormwater carries contamination from motor oils, pesticides, pet waste, and household hazardous chemicals into the river, streams, and, ultimately, the Puget Sound.
  • That's why it's important we rebuild our stormwater infrastructure so that it protects the Watershed and Sound.

Watch the Executive explain this new strategy



Teaming up to protect the Watershed

King County and the City of Seattle partnered with the University of Washington Green Futures Lab and the Bullitt Foundation to strengthen efforts to support our environment and the people who live, work, and play in our beautiful region.

We're creating a framework built by community leaders, planners, businesses and individuals who are committed to smart, regional-based and coordinated investments to improve our air, land, and water, and support our future quality of life in the Green/Duwamish Watershed.

This collaborative approach is based on the Watershed Open Space Strategy developed for the Puyallup-White Watershed.

Working together, we can achieve so much more than working alone. We can identify opportunities in the Green/Duwamish Watershed and fill gaps to achieve better outcomes that benefit local cities, forests, farms, rivers, diverse communities, and Washington state’s industrial core.

Get to know the Green/Duwamish

  • 93 miles long.
  • Covers nearly 500 square miles.
  • Stretches from one end of King County to the other, from the Cascades to Elliott Bay.
  • Upper reaches of the Watershed includes healthy forest habitat as well as the City of Tacoma's municipal drinking water source.
  • The middle portions of the Watershed offer recreational opportunities, historic and active farmlands, and thousands of acres of preserved open space.
  • The Lower Duwamish features suburban and urban areas and is home to some of the state's most important economic engines, including the second-largest warehouse district on the West Coast.
  • Native Americans have used this Watershed since time immemorial.
  • Today, the Green/Duwamish is home to some of the most economically and ethnically diverse communities in the nation.
King County Executive
Dow Constantine
Dow constantine portrait

Read the Executive's biography