All Hands In to Repair Seattle’s Polluted Duwamish River

Local groups and government agencies are working together to remediate this Superfund site in the city’s midst, despite diminishing support from the EPA.

Industrial development along the Duwamish River

Credit: Paul Joseph Brown/Ecosystem Photo

“The dangers in the Duwamish River are hidden. They’re not visible, and you can’t experience them with your senses,” says Sharon Leishman of the Duwamish Alive Coalition, which brings together nonprofits and government agencies dedicated to improving the health of this Seattle-area waterway.

Part of the group’s mission is raising public awareness of all those invisible dangers: namely, the polychlorinated biphenyls (PCBs), dioxins, carcinogenic polycyclic aromatic hydrocarbons (cPAHs), and arsenic that routinely flow into the waterway through stormwater pipes and upland runoff and have accumulated along the river’s shores during more than a century of heavy industry. The five-mile stretch that flows into Elliott Bay is so polluted that in 2001 it was declared the Lower Duwamish Waterway Superfund Site and added to the National Priorities List.

Additionally, the Washington State Department of Health has determined that the Lower Duwamish River’s crabs, other shellfish, and resident bottom-feeders harbor unsafe levels of PCBs and other chemicals. Despite warning signs posted along the Duwamish’s banks, members of riverfront communities—many of whom are immigrant populations—fish in the waterway. After all, the Duwamish doesn’t smell bad and may look relatively clean to people from areas with visibly polluted rivers, Leishman says.

In the 1980s, salmon inexplicably leapt from the Duwamish River and died (July, 1986).
Credit: Natalie B. Fobes/National Geographic/Getty Images

Restoring the Duwamish may be even more complicated than first anticipated, due to the river’s complex ecosystem, impacts from climate change, and—not least—the agenda of the new EPA head, Scott Pruitt, who has worked to abandon federal clean water regulations, loosen air pollution standards, and cut environmental justice programs. What’s more, the cleanup efforts themselves can backfire if not done with appropriate care—after all, the diesel trucks and trains used to ferry materials back and forth from the site carry their own harmful impacts. That associated air pollution is a threat that the city of Seattle is keenly aware of and has been working hard to minimize. The surrounding neighborhoods already face the region’s highest ranking for air pollution, and childhood asthma hospitalization rates in the city are twice that of the King County average.

Ultimately, the goal for river rehabilitation extends beyond its channel to the well-being of the communities that flank it. “Once the Duwamish River’s quality is on par with Puget Sound,” says James Rasmussen, director of the Duwamish River Cleanup Coalition, “area life is more equitable.”

Cleaning the River

Four entities partially responsible for the sediment contamination—the city of Seattle, King County, the Port of Seattle, and aerospace manufacturer Boeing—already have poured $200 million into initial efforts to reduce PCB levels on the Duwamish, cutting them by half since work began in 2013. Now, phase two—a $340 million undertaking—is about to begin. The work will include dredging areas prone to erosion, in some cases laying down a clean layer of sand and in other areas adding an engineered cap over remaining contamination.

After the dredging phase, the Washington Department of Ecology, working with the EPA, will address the sources of continuing pollution. “The Duwamish is the industrial heartland of King County,” says Dave Schuchardt, Seattle’s point person for the Duwamish Superfund since 2007. And while most contamination in the sediment occurred before the Clean Water Act was enacted in 1972—“when industry dumped waste down the drain,” Schuchardt says—PCBs from older buildings, such as those with aging exterior paint, are breaking down and entering the region’s water systems.

New technologies are showing promise. A pilot study is determining if activated carbon can keep low-level PCBs out of the river bottom where dead and decaying matter is snapped up by bottom-feeding fish. Researchers are hoping that the cleansing effects ripple up the food chain onto the dinner plate. Most urban waterways have some fishing advisories, Schuchardt says, but “we do expect cleanup to reduce the contamination level.”

A Change in EPA Strategy

Earlier this year, Pruitt announced he would prioritize the Superfund program. His Superfund Task Force released its initial report on July 25 after just 30 days of deliberation. Although it’s too early to tell how Pruitt’s approach may impact the Duwamish cleanup, some find the report’s focus concerning. It does not seem to support the kind of comprehensive effort underway in Seattle; rather, it emphasizes expediting cleanup efforts, cutting costs, and encouraging private investment and redevelopment opportunities.

Citizen activists working on a habitat restoration project on the Duwamish River with Boeing plant in the distance
Credit: Paul Joseph Brown/Ecosystem Photo

And little mention is made of community input or the concerns of local residents. “If you read the whole 26-page report, there’s barely mention of who lives in the community,” says Scott Slesinger, NRDC’s legislative director. “It’s all about making it easier for polluters to clean up or claim they’ve cleaned up.”

Earlier this year, President Trump also suggested a 30 percent Superfund cut. “If the president guts Superfund, it slows down the cleanup,” Slesinger says.

One result might be that the EPA funds only cheaper, less extensive Superfund cleanup work. Ten Superfund sites were selected for focus, Slesinger says, with an emphasis on those likely to be redeveloped into commercial and industrial properties rather than those involving higher risk to local communities.

As if all that weren’t enough, Pruitt’s recently announced “back to basics” agenda signals his intention to review “misaligned regulatory actions,” aims to make clean water regulation a state responsibility, and doesn’t mention climate change. By focusing solely on the past damage to Superfund sites, his plan ignores current threats to river health and those likely to come in the future.

More at Stake

Researchers are still attempting to identify and reduce pollution sources from the Green River, which feeds the Duwamish and probably contributes to the river’s pollutant load. “Existing sediment data and models completed for LDW [Lower Duwamish Waterway] cleanup studies indicate that LDW sediments may still exceed target levels after cleanup because of pollutant concentrations in sediment coming from upstream,” the Washington State Department of Ecology has reported.

Native American canoes from around the Puget Sound celebrate the Duwamish tribal longhouse.
Credit: Paul Joseph Brown/Ecosystem Photo

Even if the Duwamish is cleansed according to Superfund targets, climate change may still bring new threats to the region’s wildlife and people. For example, the endangered Chinook salmon live in a narrow temperature range. If the water warms too much, the fish die off, Leishman says.

A crisis for Chinook would also be a crisis for the members of the local Muckleshoot tribe, who retain fishing rights on the Duwamish and for whom salmon are a critical part of diet and culture. (Because Chinook migrate between the Duwamish and Puget Sound, they’re still considered safe to eat.) To address this threat, the Muckleshoot Indian Tribe Fisheries Division identified areas of the river receiving the most light and heat and created “sun maps” depicting optimal spots along the Duwamish’s banks where more trees could be planted to provide natural cooling. The tribe shared these maps with King County and other parties as part of a watershed management plan.

The river’s various stakeholders hope that integrated efforts like these will boost the likelihood of success, even if the federal government pulls back its support. “We want a place where the community can thrive and fish, and wildlife thrive, and industries thrive,” Rasmussen says. Should the river’s advocates achieve this goal, cities and towns across the United States might learn from the Seattleites’ approach to revitalizing their polluted waterways. After all, with more than 1,300 Superfund sites appearing on the EPA’s National Priorities List, the communities of the Duwamish have plenty of company.

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