Duwamish Waterway Park

The Duwamish Waterway Park (Site) is located on the west side of the Lower Duwamish Waterway (LDW) in the South Park neighborhood of Seattle. The Site is approximately 1.7 acres and includes a play area, picnic area, and beach with river access.  Seattle Parks and Recreation owns and manages the park.

Update from the Department of Health (DOH)

What did DOH conclude?

  • DOH concludes that touching, breathing, or accidentally eating sediment from Duwamish Waterway Park beach is not expected to harm people’s health. Maximum levels of contaminants in sediments are below levels of concern.

    DOH concludes that, based on the previous PHA, exposure to chemical contaminants in surface water while swimming is not expected to harm people’s health.

What does DOH reccomend?

  • DOH recommends the public follows Seattle Parks and Rec (SPR) signs at the Park on Wash Your Hands and Feet after playing in sediment or surface water.

  • DOH recommends the public follows Public Health Seattle King County (PHSKC) advisory against swimming near combined sewer overflow (CSOs) because of potentially high levels of pathogens.

  • DOH strongly advises against the use of untreated surface water as a drinking water source anywhere in the state.

 
 


What is the history and status of the Duwamish Waterway Park cleanup? 

The Duwamish Waterway Park cleanup is moving from an independent cleanup process managed under Ecology’s Voluntary Cleanup Program (or VCP for short) to the formal cleanup process which will be managed in the future by a formal site manager. During the independent cleanup process, Ecology provided technical assistance to the City of Seattle’s Parks and Recreation Department to fulfill the cleanup requirements under Washington State’s environmental cleanup law – the Model Toxics Control Act (or MTCA for short).  Ecology’s technical assistance to Seattle Parks included reviews of investigations and cleanup actions as well as guidance on how to address any data gaps in Seattle Park’s work so that they could fulfill MTCA’s cleanup requirements and achieve a “No Further Action” designation from the VCP program.

 

Both the independent and formal cleanup processes can fulfill MTCA’s requirements to protect human health and the environment. Under the independent cleanup process through the VCP program, technical assistance is provided but applicants are not required to follow Ecology’s technical assistance.  Through the formal cleanup process a legal agreement directs the cleanup, this legal agreement enables Ecology to regulate the cleanup with formal oversight which includes a scope of work and schedule of actions that will be required to complete the cleanup process.

 

The formal cleanup process begins with Ecology establishing “Potentially Liable Persons” (or PLPs). Ecology is in the process of sending PLP letters now. After Ecology mails these letters, we will begin negotiations with these parties to reach a legal agreement that defines the scope of work of the cleanup. Once the draft legal agreement is ready, Ecology will seek input from the community during a public comment period.

What are the chemicals at the site and how toxic are they?

Response

Investigations at the Duwamish Waterway Park have confirmed contamination levels exceeding MTCA cleanup standards set to protect human health and the environment.

 

·      Contamination in the soil include: Arsenic, lead, mercury, other metals, both chlorinated and non-chlorinated organic chemicals, polychlorinated biphenyls (PCBs), and carcinogenic polycyclic aromatic hydrocarbons (PAHs).

·      Contamination in the surface sediments include: Arsenic, lead, copper, and chlorinated organic chemicals. (That’s the in-water sediments in the Lower Duwamish Waterway.)

 

The toxicity of these contaminants depends on many variables including the different ways that people, pets, and our environment are exposed to these contaminants. The formal cleanup process will address this contamination as well as the exposure pathways.


What happens next?

After Ecology mails the Partially Liable Parties (PLP) letters, we will begin negotiations on the legal agreement and then schedule a public comment period for the legal agreement. The outcome of those next steps will set the stage and schedule for the completion of the Site cleanup under MTCA.  The cleanup of the Duwamish Waterway Park site will continue under the formal cleanup process much in the same way as the other formal Lower Duwamish Waterway (LDW) cleanup sites. That involves a public involvement process and cleanup coordination with EPA’s LDW Superfund Site which includes a 5-mile stretch of the Duwamish River that flows north into Elliot Bay. Ecology is working to stop or reduce sources of contamination to the LDW Superfund Site, an effort known as “source control,” so that EPA can proceed with the cleanup of the river sediment.

 

Cleanup of the Duwamish Waterway Park site will be another part of that source control effort.


Site Documents
Electronic documents are available for this site, click “View Electronic Documents” in the right-hand column. Click for instructions on how to submit a public records request.

Check out What’s In My Neighborhood to find out about other cleanups in your area. 

Read here community comments

INFORMATION ON MEETINGS:

April 13 Meeting-

ADDITIONAL RESOURCES