The Lower Duwamish River

The Green-Duwamish River flows north from the Cascade Mountains all the way to Elliott Bay, by Seattle, Washington. At Tukwila, the Green River becomes the Duwamish River. The Lower Duwamish River is the five-mile section leading into Elliott Bay.

The Lower Duwamish River was once a wide, meandering river, with thousands of acres of mudflats and wetlands, that flowed into Elliott Bay and supported a variety of habitat for fish and wildlife. Industrialization transformed the Lower Duwamish River to a channelized waterway, destroying 97 percent of the original habitat.

Straightening the Lower Duwamish River allowed ships to navigate to industries along the river's shores, but also filled in mudflat and marsh habitats and replaced river bends with factories and shipping yards. The process also made the straightened channel unnaturally deeper, so that ships could pass through.

Since the 1900s, hazardous substances have been released from commercial industries along the river, injuring fish, birds, wildlife, and their habitats.

Through the Natural Resource Damage Assessment (NRDA) process, the Elliott Bay Trustee Council is working to assess injuries to natural resources and restore habitat in the Lower Duwamish River.

Explore this story map to learn more about the history of the Lower Duwamish River, the Elliott Bay Trustee Council, and the restoration work that is helping the river's natural resources recover and thrive.

Native people have lived in the Duwamish River valley since time immemorial. They have harvested fish and shellfish for food and continue to see the river as an important cultural, subsistence, and recreational resource.

As industrialization of the Lower Duwamish River grew, businesses were built along the river's shorelines. Many of these businesses participated in practices that polluted the water and sediment, and reduced habitat.

The Lower Duwamish River NRDA case refers to three different Superfund sites: Lockheed West, Harbor Island, and the Lower Duwamish Waterway. The Lower Duwamish Waterway was declared a Superfund site by the U.S. Environmental Protection Agency (EPA) in 2001. The  EPA  and  Washington Department of Ecology  have key roles in the cleanup effort by controlling sources of pollution in this industrial waterway.

Contaminants released into the river are also found in fish, which has led to  fish consumption advisories  warning people of the health risks from consuming fish and shellfish in the Lower Duwamish River. This means that recreational and subsistence fishing opportunities have been lost or diminished.

Learn more about the history of the Lower Duwamish River by exploring our  previous story map .

Through the NRDA process, the Elliott Bay Trustee Council is responsible for restoring natural resources impacted by contamination in the Lower Duwamish River on behalf of the public. The Trustee Council includes representatives from the Muckleshoot Indian Tribe, the National Oceanic and Atmospheric Administration (NOAA), the Suquamish Indian Tribe of the Port Madison Reservation, the U.S. Department of the Interior, the Washington Department of Ecology, and the Washington Department of Fish and Wildlife.

Federal laws, including the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Oil Pollution Act (OPA), give the Trustees the authority to act on behalf of the public as part of the NRDA process. NOAA is the lead administrative trustee for the Lower Duwamish River NRDA case.

The Trustees are currently working to restore natural resources injured by contamination in the Lower Duwamish River. By continuing to reach settlements through the NRDA process with those responsible, the Trustees design projects that will restore habitat and resources injured by pollution. A lot of work has been done, and there is a lot more to do.  In 2019, the Trustees finalized an updated natural resource  Injury Assessment Plan . The updated plan outlines the approach to assess impacts on natural resources through additional studies and analysis.

To support early restoration efforts, the Trustee Council formalized their decisions about the types of restoration needed to address injuries to natural resources in the  Lower Duwamish River NRDA Restoration Plan and Programmatic Environmental Impact Statement  in 2013. This plan outlined the need for marsh, mudflat, and riparian habitats that are integrated together as much as possible, within the Lower Duwamish River. These efforts will help to restore habitat for fish, birds, and other wildlife impacted by pollution from industries along the river.

The restoration projects shown in the map below include those implemented as part of the Lower Duwamish River NRDA thus far. Some of the more recent restoration projects are highlighted in the sections below, including Boeing Plant 2, Bluefield Site 1, Vigor's West Waterway Habitat Bench, and Vigor's Southwest Yard.

Community outreach and public participation are important components of the Trustees' restoration planning process.

The Elliott Bay Trustee Council has held a series of public meetings to provide updates to the public on restoration planning activities and gather input on the scope and scale of restoration. A report published in 2007 summarized the  early scoping work  completed for the Lower Duwamish River NRDA. The Trustees have also released a number of documents for public review and comment, including the  2013 Restoration Plan and Programmatic Environmental Impact Statement , the  2019 Injury Assessment Plan , the  2021 Restoration Plan / Environmental Assessment for the Vigor Shipyards Habitat Projects , the  2021 Restoration Plan / Environmental Assessment for Bluefield Site 1 , and the  2024 Restoration Plan / Environmental Assessment for General Recycling of Washington Habitat Project .

Members of the Elliott Bay Trustee Council also participate in EPA's Lower Duwamish Waterway Tribes, Trustees, and Community quarterly meetings. These meetings are open to the public and are intended for the Tribes, Natural Resources Trustees, and community members to learn about and discuss issues regarding the cleanup of the Lower Duwamish River.

NOAA's  Community-based Restoration Program  has also funded community stewardship efforts along this important working waterway. For a more comprehensive list of NOAA restoration projects funded in the Lower Duwamish River, see NOAA's  Restoration Atlas .

While the restoration projects described above have begun to restore habitat for fish, birds, and other wildlife along the Lower Duwamish River, there is more work to be done. The Elliott Bay Trustee Council continues to work with potentially responsible parties to implement restoration projects that address the injuries and harm done to natural resources. This future restoration work will be aligned with the priorities that the Trustees outlined in their 2013 Restoration Plan. All restoration sites will have monitoring plans to track progress and ensure projects provide benefits to fish and wildlife as designed. Additionally, legal agreements and required upfront funding provide assurances for the stewardship of each site long into the future.

We anticipate future opportunities for community engagement and we look forward to continuing our work to assess and restore for injuries to the Lower Duwamish River.

To stay up to date on the latest Lower Duwamish River restoration on behalf of the Elliott Bay Trustee Council, you can opt to join our  newsletter  or check our  webpage . To receive the newsletter, enter your email at  this link  and click "Lower Duwamish River" under West Coast Updates.