Alaskan Way Seawall
The Alaskan Way Seawall is a seawall which runs for approximately 7,166 feet (2,184 m) along the Elliott Bay waterfront southwest of downtown Seattle from Bay Street to S. Washington Street. The seawall is being rebuilt in the 2010s as part of a waterfront redevelopment megaproject estimated to cost over one billion dollars.
The seawall was built to provide level access to Seattle's piers and supports the Alaskan Way Viaduct and Alaskan Way itself, which is a surface street. Completed in 1934, the seawall was built on top of wood piling.
Despite efforts to prevent marine pest damage when the seawall was designed, after the 2001 Nisqually earthquake, SDOT found that gribbles had consumed all the wooden supports in some places.
In addition, everything behind the seawall from Alaskan Way to Western Avenue is built on top of fill, making for a very dangerous situation should a large earthquake occur.
The viaduct itself has been considered particularly at risk; the Washington State Department of Transportation states that there is a 1-in-20 chance that it could be shut down by an earthquake within the next decade, and so plans have been underway to replace both seawall and viaduct.
The seawall rebuild project was estimated to cost $350 million as part of an overall waterfront redevelopment budgeted in 2012 at $1.07 billion. Construction began in 2013 and it is scheduled to be complete in 2017, more than a year late and costing $409 million as of September 2015[update].
Coordinates: 47°36′16″N 122°20′21″W / 47.60444°N 122.33917°W
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