Editorial: Historic pollution, epic cleanup on the Lower Duwamish
Cleaning up the Lower Duwamish Waterway requires a plan and a timeline to match the challenges of remediating a century of pollution.
Seattle Times Editorial
Learn about EPA’s cleanup plan and testify on the proposal Tuesday, April 30, 3:30 p.m. and 6:00 p.m. at South Seattle Community College–Georgetown Campus, 6737 Corson Avenue S. For details, visit
SINCE 2001, the five-mile stretch of river known as the Lower Duwamish Waterway has also been known by a horrific shorthand: Superfund site.
The designation is reserved for the nation’s most polluted locations. A cleanup plan has been a decade in the making, and the public is invited to comment on the proposal.
Broadly speaking, two pathways are available: clean and cleaner. What is the reasonable expectation for the natural health of a region that is home to 100,000 jobs, 38,000 residents and 25 percent of King County manufacturing?
The historic layers of sediment and crud include a century of industrial discharges, stormwater runoff and combined sewer overflows.
Elements of the cleanup have been under way, but going ahead what should be the mix of dredging to remove sediment, engineered caps over the sediment and carbon treatment of the layers of effluent?
The EPA’s estimated cost is $305 million for a program that could take seven years once it eventually begins. The Lower Duwamish Waterway Group — of King County, city of Seattle, Port of Seattle and Boeing — back a plan with an estimated $270 million price and shorter timeline.
A schedule that maximizes cleanup technologies, speaks to the realities of an urban environment and acknowledges the need to keep an industrial area functioning is realistic.
The Duwamish cannot be reclaimed as a pristine waterway, but the natural bounty of the waterway ought not be a hazard to human health. Public meetings are planned for April and May.