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Seattle Residents and Juvenile Salmon Using and Enjoying New Pocket Beach

This photo shows the entire pocket beach at low tide. At the lower end is an exposed portion of the habitat bench. This bench extends the length of the shoreline (1200 feet). It is habitat for juvenile salmon that migrate along the shoreline in the spring on their way out from rivers to the ocean.

These fish need shallow water (less than six feet deep) to avoid predators mainly larger fish. They migrate primarily in the intertidal zone. Elliott Bay where the project is located lacks a continuous intertidal zone due to filling and dredging for navigation and waterfront development. The habitat bench was built in conjunction with the pocket beach and as part of the seismic buttress for the existing seawall south of the pocket beach.

The project restored intertidal habitat in two ways by building these two features which project monitoring has shown are preferred over rock rip rap by juvenile salmon. There are several species of salmon and seagoing trout that are listed as endangered species by the federal government in Puget Sound. Puget Sound Chinook (or King) salmon are one of these species and they have been documented using this site.

The normal (mean of daily higher high tides) is almost 12 feet. The extreme range is 18 feet (+14 for high above MLLW and -4 below MLLW). Most of the driftwood arrived naturally. There were some drift logs placed further back that are used as benches. We designed the beach with a backshore above the normal daily high tides but below the extreme high tides where most driftwood is deposited. This is typical of natural Puget Sound accretion beaches.