The Duwamish River once meandered through a tidal wonderland of wetlands, sloughs, side channels and oxbows — some 5,300 acres of habitat for wildlife, including salmon, birds and a banquet of insect and invertebrate life.

That all started changing with the arrival of settler-colonizers questing for flat land for development. Beginning in the early 1900s, the Duwamish was steadily straightened, dredged and filled.

Harbor Island — entirely made from fill — and the Lower Duwamish Waterway today are home to more than 80% of Seattle’s industrially zoned land, up to 80,000 industrial and manufacturing jobs, and an annual payroll of about $2.5 billion, said George Blomberg, environmental planner for the Port of Seattle, as he piloted a recent boat tour of the river.

With all that prosperity has come pollution, managed today under multiple Superfund cleanups in the river and on its banks, overseen by the U.S. Environmental Protection Agency.

Now new plans to complete a cleanup where the Duwamish meets Elliott Bay and Puget Sound are under discussion, and contested.

The East Waterway is part of the larger Harbor Island Superfund site. The 157-acre cleanup area stretches for 1 mile, and is located immediately downstream and north of another Superfund site, the Lower Duwamish Waterway.


Sediments at the bottom of the waterway contain 29 contaminants in all, including polychlorinated biphenyls and mercury, which pose risks for invertebrates that are the base of the food chain. PCBs also pose risk to fish.

Most of the East Waterway will be dredged to remove contaminated sediment. The cleanup could cost up to $400 million and take three to five years to design and eight to 10 years to complete.

Managers at the EPA, Port, city and King County — the responsible parties in the cleanup — have argued that goals set in 2014 for the Lower Duwamish Waterway cleanup, right upstream and now underway, are unrealistic. They have discussed weakening levels for PCBs, arsenic, dioxins and furans.

But setting a lesser standard in the same river creates an artificial boundary, and doesn’t make sense, said Paulina Lopez, a South Park resident and executive director of the Duwamish River Community Coalition, or DRCC. “Is there supposed to be a sign that says, fish, turn around here?” she said.

Communities of color in the Duwamish Valley already face disparities in environmental justice that burden them with higher health risks, said James Rasmussen, who is Duwamish and Superfund director for the DRCC. “This is a sacrifice zone,” he said of the river valley.

It’s better to keep pressure on with higher standards and clean up the surrounding areas, Lopez argued. The DRCC pushed back last summer at settling for less when it comes to the East Waterway.


“They are supposed to protect us,” she said of the EPA.

How clean is clean?

Brock Milliern, program manager of the toxic cleanup program at the state Ecology Department, said the agency agrees with the community coalition. “It is incredibly important that we keep our standards high,” Milliern said.

“Maybe somewhere decades down the line we assess, and say we have done everything we can. But we are not there yet, and we need to keep our sites on the best possible outcomes.”

Seattle’s mayor, the King County executive and Port Commission president wrote the EPA Region 10 acting administrator in September, insisting on a timeout for more community engagement to guide formation of the plan. EPA has agreed.

“EPA is taking time … to consider state and community concerns and allow for more community engagement, education and outreach to occur,” said Tim Carroll, spokesman for EPA, in an email. “This approach aligns with the Administration’s priorities to protect public health, and incorporate environmental justice considerations and increased community engagement into the work we do.”

Magdalena Angel-Cano, community engagement and communications specialist with the DRCC, said the fight with EPA over the waterway has come at a particularly bad time for the community. “EPA should be walking with us, not our adversaries,” she said. “And all this during a pandemic, when our community is struggling to pay rent, to work, to take care of our families. These are the things we need to be taking care of.”


Angel-Cano, 22, was in the first cohort of youth cleanup workers on the Duwamish. Today she is a spokeswoman for the DRCC. Along the banks of the Duwamish, she has found purpose and passion.

The community is counting on a cleanup that makes the river fishable, and the environment safe and inviting, Angel-Cano said. “The Latinx community is really united; we want to continue to stay here. We don’t want to leave, because it is home.”

Progress is being made on the river.

As part of the cleanups, the Port has removed tons of contaminated soil and sediment, hauled away derelict vessels, uprooted creosoted pilings, torn out old shoreline armoring, planted native plants, and developed pocket parks and viewing platforms along the waterway — including a new shoreline park opening in South Park in spring 2022.

EPA estimates that since 2012, average levels of PCBs in Duwamish Waterway sediments have been reduced by half.

The Port is striving for coexistence, even in so highly altered an environment, Blomberg said. “We will never turn back the clock. But at least we are making progress.” The Duwamish, after all, is home to more than industry.

As the crew from the Port boated past cleanup sites, sea ducks lifted from the water. Seals and sea lions barked and lounged and swam. Light poles in shoreside parking lots bristled with osprey nests. An angler tried his luck from the banks.


Not just an industrial powerhouse, this place is a cherished home for people, and a crucial fishery, protected by rights reserved by the Muckleshoot and Suquamish tribes in their treaties with the United States.

Problem of a persistent pollutant: PCBs

At the heart of the East Waterway cleanup controversy are PCBs: a widely used suite of toxic, man-made chemicals banned more than 40 years ago, but stubbornly persistent in the environment. A recent study predicted a global killer-whale population collapse because of PCBs in the orcas’ food chain.

PCBs were used around the world for decades, primarily to insulate and cool electrical equipment and prevent electrical fires. They were also used in hydraulic systems, lighting and cable insulation, paint, caulking, sealants, inks and lubricants. Today PCBs still leach, leak and dissipate into the atmosphere and contaminate runoff during rainfall.

Southern resident orcas are at more grave risk of health effects from PCBs than other orca populations in the world because they live in more polluted waters — including Puget Sound, where they routinely hunt Chinook and chum salmon. The Green River, which flows into the Duwamish, is one of the most important food sources for the southern residents.

Biologist Peter Ross shocked the world in 2020 when he tested the blubber of southern resident killer whales and determined they were among the most polluted cetaceans on Earth.

“A silent crisis to me is very much where we are at,” said Ross, senior scientist and director of the Healthy Waters Program at the Raincoast Conservation Foundation, a B.C.-based science and conservation nonprofit.


“We have almost forgotten about pollution if it is not plastic or debris or an oil spill. People are oblivious, overwhelmed with bad news; we have fallen asleep on what chemicals are getting into our wastewater and our waterways.”

The Duwamish and Puget Sound are particularly vulnerable to retaining pollutants, Ross noted.

Since its extensive alteration, the river doesn’t move a massive volume of water like Canada’s Fraser River, cascading sediment from the mountains to the lowlands, naturally burying polluted sediments. Puget Sound also is the most urban of all the fjords in North America, with millions of people affecting its water quality. Its underwater geography also includes sills that in places impede cleansing water exchange.

Puget Sound salmon have been found by senior researchers Jim West and Sandra O’Neill at the Washington Department of Fish and Wildlife to be the most PCB-contaminated salmon on the West Coast. The team also is seeing some of the highest levels of PCBs in the world in herring sampled at Quartermaster Harbor, at Vashon Island.

Where are the PCBs coming from? The food chain is their current thinking, not just contaminated sediments — and the Duwamish is a superspreader.

“This is the only situation where we have a major river running smack through a Superfund site,” said West. “It’s not like it’s a single pipe; it’s a major river that has dissolved and particulate PCBs coming out if it.”


The team is broadening its view of the biological impact zone of PCB pollution from the Duwamish to investigate the process and geographic extent of so-called bioaccumulation, in which pollutants travel and concentrate as they move up the food chain.

“The English sole are saying this is where the pollution is starting [in the Duwamish], the herring are saying this is where it is going [in Puget Sound], and the killer whales are saying this is where it is ending up,” West said.

For that reason, as planning for the cleanup continues, establishing two levels for final PCB levels in the river should be avoided, O’Neill said. “There is not an animal I am aware of that knows the difference between the Lower Duwamish and the East Waterway. This is the migration area and their feeding area, and they are going to move around.”

All of the work upstream to clean up the waterway can be undermined by salmon milling in less clean water elsewhere in the river, O’Neill said. “In general, think of those rivers as arteries to the rest of the body, and they are bringing contaminants to our pelagic (open water) food web. The more you do to reduce that flow of contaminants, the better it will be.”