June 4, 2019 — Next time you’re visiting Seattle’s downtown waterfront and gazing out across Elliott Bay toward the majestic Olympic Mountains, look down. You might see a shoal of silvery baby salmon, each about 3 inches long.
You might also see a snorkeler counting fish, because University of Washington researchers are studying habitat improvements built along the city’s $410 million new seawall, which stretches 3,100 feet between the Seattle Aquarium and the Colman Dock ferry terminal.
Their observations are preliminary — yet promising. Since the wall was completed in 2017, the School of Aquatic and Fishery Sciences researchers have repeatedly witnessed juvenile salmon swimming under the wooden piers that extend out over the waterfront, where they almost never ventured before.
During the wall’s construction, workers added shelves and grooves meant to help algae grow and critters like mussels take hold. They laid rock beds below the wall because young salmon prefer to forage and hide in shallow-water nooks. They even installed translucent glass panes in a cantilevered sidewalk between the wall and the piers to allow light through, down to the water.
Juvenile salmon prefer swimming and eating in sunlight, and the improvements are meant to act like a migratory highway, complete with rest stations and restaurants. Taken together, they represent what might be the most sweeping seawall habitat-restoration project anywhere.