The Seattle Department of Transportation, working with the U.S. Army Corps of Engineers, is replacing the failing seawall in downtown Seattle, providing the foundation and structural support for a new waterfront.

In 2010, The Seattle Department of Transportation selected Tetra Tech to provide planning, engineering, and environmental support for this high-profile project. In addition to protecting the waterfront, replacing the seawall provides opportunities to restore fish habitat and reconnect people to the water.

The seawall replacement project is a priority for these reasons:

  • The Elliott Bay seawall, built between 1916 and 1934, has deteriorated significantly
  • The seawall was not designed for earthquakes and could fail during a moderate to large earthquake
  • Failure also could be caused by wind driven storm waves or the erosive tidal forces of Elliott Bay
  • The seawall supports major utilities, Alaskan Way and SR 99, the ferry terminal, and rail lines

The seawall will be built to current seismic standards. As its design begins, the alternatives include the following elements: the location of the seawall, a structural solution, habitat enhancement measures, a restored roadway and pedestrian/bicycle facilities, and flexibility for design of the central waterfront area (inland from the seawall). The new seawall alignment will vary along the waterfront depending on the existing wall type.

For more information, visit the project website to hear about our latest activities.