Duwamish Waterway Sediment Remediation and Habitat Project | Boeing Plant 2, Seattle, WA

DOF provided design and construction management services to implement a sediment remediation and habitat enhancement project within the Lower Duwamish Waterway Superfund site, where marine sediment had become contaminated with PCBs. Elements of the project within this urban river included dredging, offsite transload of dredged material, and backfill and restoration of dredged areas. Completed between 2013 and 2015, the project received the 2016 WODA Environmental Excellence Award for Environmental Dredging.

DOF provided the following services:

  • Dredging design
  • Development of remedial dredging methods to reduce and eliminate residuals
  • Construction oversight for dredging, backfill, and shoreline work
  • Construction management
  • Preparation of construction documents
  • Negotiations with agencies and other stakeholders