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Green-Duwamish Watershed Strategy


King County Executive
Dow Constantine

Executive Constantine, Mayor Murray announce Green/Duwamish Watershed Strategy


King County and the City of Seattle will coordinate work by governments, nonprofits, and businesses across the 500-square-miles of region's critical watershed, which stretches 93 miles from the Cascades to Elliott Bay.


Green/Duwamish Watershed Strategy

Photo by King County

Building upon the more than $1 billion already invested, or committed for investment, by King County and the City of Seattle for clean-up of the Green/Duwamish Watershed, King County Executive Dow Constantine and Seattle Mayor Ed Murray announced an ambitious strategy that will coordinate work by governments, nonprofits, and businesses to improve the health of that 500-square-mile watershed.

The Green/Duwamish Watershed Strategy is aimed at producing tangible improvements for cleaner air, land, and water, by coordinating the work being done and money being invested across the entire ecosystem of cities, forests, farms, and rivers.

The strategy will use the best available science and take advantage of emerging technologies to deliver the best possible outcomes for County and City investments. The strategy includes the building of a coalition that is committed to improving human health, water quality, open space, land use, and the vitality of the Watershed’s community and economy.

The strategy includes a series of new actions to be taken over the next few years:

  • King County will join the Environmental Protection Agency, City of Seattle, Port of Seattle, and The Boeing Company to launch a pilot study to test the effectiveness of using activated carbon – similar to a household water filter – as a clean-up tool in the Lower Duwamish.
  • King County will acquire more than 100 acres of property at five locations along the Green and Duwamish rivers that are vital for salmon habitat, forested wetland protection, and reducing flood risks, with a proposed $3.4 million in Conservation Futures funds.
  • Community-led projects, funded by a proposed $2.1 million from wastewater funds in King County's WaterWorks Grant Program, that improve water quality through clean-up and control of new pollution at the source.
  • King County’s Green Grants Program will fund $102,000 of community-led projects that control new and ongoing sources of pollution, prepare for the effects of climate change, and improve air quality in Watershed neighborhoods. 

To ensure long-term results, the strategy will control pollution at its source, including legacy contamination that continually washes off previously contaminated buildings and lands. It will also control fresh runoff of motor oil, pesticides, pet waste, and household chemicals that flow into streams, rivers, and, ultimately, the Puget Sound.  

Over the next 18 months
King County and Seattle will partner with the University of Washington Green Futures Lab and Bullitt Foundation to convene a Watershed stakeholder advisory group. This group will coordinate the work already being done by local, state, and federal agencies to manage toxic-site clean-ups, habitat restoration, salmon recovery, flood control and stormwater infrastructure, open space preservation, economic development, and more.

At the table will be environmental groups, community representatives, business leaders, trade unions, urban planners, public health organizations, regulatory agencies, and elected officials.

Building on previous efforts
King County and Seattle have already committed $524 million for projects in the Lower Duwamish area, and this strategy builds upon work that's already been done or is under way in the Watershed, including:

  • Removal of historic sediments in the Duwamish River,
  • Controlling overflows of stormwater and sewage during heavy rains,
  • Control of pollution from business and industry,
  • Water quality monitoring,
  • Environmental studies, and
  • Habitat restoration.

Relevant links


I've lived around the Duwamish River my entire life, and restoration of this watershed is something I very much want to see happen in my lifetime. This strategy will coordinate the work we're doing and the money we're investing across the entire ecosystem – including property acquisition, grants for community-led projects, and testing of emerging technologies for clean-up of historic sediments.

Dow Constantine, King County Executive

The Duwamish Superfund site is part of a much larger watershed that spans 93 miles from Elliott Bay to beyond the Howard Hanson Dam. In order to have a clean river, we need a healthy system. It's time for a broader conversation and a broader strategy.

Ed Murray, Seattle Mayor

Together, we can make sure that the watershed work serves broader justice and equity goals. New policies will help to ensure that people have access to the same level of opportunity to fulfill their potential, regardless of race, income, and neighborhood.

Joe McDermott, King County Councilmember

For more information, contact:

Chad Lewis,, 206-263-1250

King County Executive
Dow Constantine
Dow constantine portrait

Read the Executive's biography