After Eight Year Hiatus, Chinook Salmon Return to Seattle Public Utilities Restoration Site to Spawn

In late October, for the first time in eight years, SPU staff observed and filmed a pair of Chinook salmon laying eggs (spawning) in a SPU-restored part of Seattle’s Thornton Creek.

SPU’s Thornton Creek Confluence project, completed in 2014 for $8 million, provided flood control in the Meadowbrook neighborhood and resilient creek habitat for salmon. SPU replaced 1,000 feet of “ditched” streambed with a wider, engineered streambed to keep high-quality gravel in place for spawning salmon.

Last month’s Chinook salmon observations indicate that SPU’s restoration project is working. SPU’s urban creek biologist Katherine Lynch praises the unique project: “We engineered the streambed vertically and horizontally. Four years after construction, it is maintaining very high-quality gravel. The Chinook salmon pair travelled almost one and a half miles to select this site for spawning. That’s a vote of confidence!”

Puget Sound Chinook salmon are listed on the Endangered Species Act and a major food source for Puget Sound’s endangered resident Orca whales. Chinook salmon need large, clean, loose gravel to build nests (redds) for their eggs.

For the first time in eight years, Chinook salmon have been spotted spawning in a SPU-restored area of Thornton Creek.

It’s Salmon SEEson!

Each fall, salmon return to streams and rivers around Puget Sound to spawn. Find out where you can view spawning Coho and Chinook salmon and learn from at bit.ly/salmonseeson.