Beginning in the early 1900s, industrial and municipal activities along the lower Willamette River in Portland, Oregon, released and continue to release dozens of contaminants into the river and surrounding environment. Substances released include, but are not limited to, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), heavy metals, butyltins, insecticides (e.g., DDT and its breakdown products DDD and DDE), herbicides, dioxins, furans, and semi-volatile organic compounds. Many of these contaminants harm the environment for many decades. Even small amounts of these contaminants can be hazardous to fish and wildlife. Larger animals like bald eagle and river otter that have eaten contaminated smaller animals (e.g., fish) can build up high levels of contamination from these prey items.
In 2000, the area of the lower Willamette River known as Portland Harbor was declared a federal Superfund site. The Portland Harbor Superfund study area extends from river mile 1.9 (between the Multnomah Channel and the Columbia River) to river mile 11.8 (near the Broadway Bridge in Portland). The EPA is the lead agency responsible for remedial actions for contaminated river sediments at the site and the Oregon Department of Environmental Quality is the lead agency responsible for remedial actions in the upland portions of the site, focusing on source control to reduce the amount of contamination entering the river.
Natural resources potentially affected by the release of hazardous substances at the Portland Harbor Superfund site include migratory birds, mammals, and anadromous fish, including species listed under the federal Endangered Species Act. Migratory birds potentially impacted by hazardous substance releases at the site include fish-eating species (e.g., bald eagle, osprey, and mergansers), swallows, and shorebirds. The river provides a critical migratory corridor for both juvenile and adult anadromous fish and juvenile rearing habitat for several anadromous fish species, including endangered stocks of Pacific salmon. The area holds great importance to Tribes as a natural and cultural resource. The lower Willamette River also is a popular area for recreation, including fishing and boating.
The Portland Harbor Natural Resource Trustee Council began a cooperative natural resource damage assessment with potentially responsible parties in 2008, and that cooperative process is ongoing. The Trustee Council concurrently is engaged in restoration planning and implementation.