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Officials Agree on $4-Billion Seattle Tunnel

Aug. 11, 2010
2 min read

Washington Gov. Christine Gregoire, King County Executive Ron Sims, and Seattle Mayor Greg Nickels have announced their recommendation to replace the central waterfront portion of the Alaskan Way Viaduct and Seawall. The recommendation includes an approximately 1.7-mile bored tunnel through downtown, a new waterfront surface street, transit investments, and downtown surface street improvements.

The tunnel would be bored beneath the western edge of downtown, under First Avenue, which should allow the current viaduct to remain in use during tunnel construction. That's important, because the mile-long viaduct section of Highway 99 on the Seattle waterfront is 55 years old and carries about 100,000 vehicles a day. The viaduct was damaged in the 2001 Nisqually earthquake and has been deteriorating since then.

Previously, transportation officials had recommended either another elevated highway or improved surface streets. But interested parties, including the Seattle Chamber of Commerce, favored a tunnel, which is the most expensive option at more than $4 billion. The elevated and surface plans would cost more than $3 billion. The state has committed $2.8 billion for the project.

The plan must pass muster in the Legislature. Also, an opposition group calling itself "Yes Viaduct!" has 180 days to gather 18,000 signatures to put its proposal opposing the tunnel before the City Council. The council could enact the construction ban into law, send it for a vote of the people or put two options on the ballot.

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