The Portland Harbor Superfund site extends roughly from the Broadway Bridge to Sauvie Island. The U.S. Environmental Protection Agency (EPA) declared Portland Harbor a Superfund site because of chemical contamination in sediments on the river bed.
According to the Oregon Health Authority, with the exception of two areas, Willamette Cove and the Gasco site, the levels of chemicals found in the water, dirt and sediment do not pose a health risk for recreational users, including children.
For a summary of health risks the Portland Harbor Superfund Site, view OHA's Portland Harbor Health Assessment fact sheet
Find more information about contamination at Willamette Cove (located at the foot of N Edgewater Street or River Mile 6.8) view OHA's Willamette Cove fact sheet
For more information about contamination at the Gasco site (7900 NW St. Helens Road or River Mile 6.5) view page 2 of OHA's Portland Harbor Health Assessment 2011 report