Seawall Project

Photo shows vehicles exiting from a ferry to Alaskan Way South, a road that has one lane in each direction.

There's more to the Elliott Bay Seawall than a new structure – the new seawall not only protects our working waterfront, but also restores the function of a natural shoreline and serves as the foundation for Seattle's future waterfront

A diagram explains the seawall layers. From top to bottom there is a light penetrating surface, a zee panel that allows space for habitat, a face panel that incorporates texture, a habitat shelf that lets vegetation grow and a marine mattress that creates shallower water.

Several structural elements make up the new seawall, including light penetrating surfaces, face panels and more

Photos show the seawall with yellow lines identifying high tide and a second yellow line above identifying “high high” tide.

The new face of the seawall was moved inland 10-15 feet to provide enough room for construction, and to create additional space for the project's habitat enhancements

Photo shows people walking on a sidewalk with a light penetrating surface, including a family with a stroller next to green leafy plants.

The old sidewalk was replaced with light-penetrating surfaces that allow natural sunlight through to the water below

Photo shows fish swimming by the seawall, which is lit by the sun.

Getting sunlight to the water is important for encouraging habitat growth and lighting the way for migrating salmon

ABOUT THE PROJECT

In 2017, the City of Seattle completed the new Elliott Bay Seawall that will last more than 75 years and improve the lost nearshore environment. Prior to the start of the Seawall Project, the existing seawall had protected Seattle for more than 70 years, but time and a harsh marine environment weakened its structure.

The new seawall has been built to meet current seismic standards, protecting public safety and acting as the foundation for Seattle’s new waterfront. The seawall also includes habitat enhancements to restore the salmon migration corridor and improve ecosystem productivity. All seawall features were designed to be integrated with other key Waterfront Seattle improvements, including the future park promenade, the rebuilt Pier 62 and Pier 58.

Habitat Improvements

When Seattle's existing waterfront was developed, Elliott Bay lost many of its natural habitat features for fish, including sloping beaches, crevices and vegetated hiding places for salmon. Seattle's new seawall was built to improve marine habitats, with a special focus on encouraging juvenile salmon migration. The new seawall face includes grooves and nooks to promote algae growth, rock beds in the bay floor for fish to hide and forage in and a light-penetrating surface in the sidewalk above to provide light for young salmon during their migration.

Researchers from the University of Washington's School of Aquatic and Fishery Sciences have been observing salmon returning to the downtown waterfront since the seawall was completed in 2017, spotting 10,000 juvenile salmon in a single day in May 2018. To learn more about how the seawall has helped enhance marine habitats, you can read this Seattle Times article: "Salmon merging onto new ‘highway’ in Seattle, complete with rest stops and restaurants".

How we built it

Construction on the new seawall began in 2013 and was completed in 2017. The new seawall was built 10-15 feet eastward of the old seawall to accommodate construction and create additional space for habitat. Click through the slider to learn more about the construction process!