The City of Tacoma’s Environmental Services Department will begin sediment cap maintenance work in the Thea Foss Waterway this summer to protect water quality and maintain the long-term benefits of the historic Superfund cleanup which was completed in 2006.
Over a century of industrial activity in the area led to contamination of sediments in the Thea Foss and Wheeler-Osgood Waterways. In response, the City of Tacoma led a $105 million cleanup effort, completed in partnership with federal and state agencies, property owners, and other responsible parties. As part of the cleanup, over 425,000 cubic yards of contaminated material was removed or capped from the waterways.
As part of the City of Tacoma’s ongoing stewardship of this revitalized waterway, two sediment cap areas (referred to as RA 3 and RA 8) will be repaired to address signs of erosion. These repairs are critical to ensuring the long-term effectiveness of the caps which isolate contaminants, prevent sediment movement, and support aquatic habitat.
More information is available at tacoma.gov/city-projects.