The biggest single contract ($1.35 billion) in Washington State history, was awarded on Friday, January 7, 2011 to Seattle Tunnel Partners to replace the Alaskan Way Viaduct with a bored tunnel. With incentives, the maximum amount of the contract could grow to $1.42 billion. The tunnel will be 52′ in diameter, the largest in the world. The project is scheduled to be completed by the end of 2015. The contractor team is lead by Dragados USA (a Spanish contractor) with experience with similar projects such as a 49.5′ diameter tunnel in Madrid Spain. Seattle Tunnel Partners is committing to delivering the project on time and on budget. A welcome commitment for local, but skeptical taxpayers.
Ten years ago after the Nisqually earthquake, it became apparent that to protect public safety, the Viaduct had to be replaced. There were two (2) options at that time. One was to tear down the Viaduct and not replace it. That option would have congested Interstate 5 and Seattle surface streets with traffic, jeopardizing the local economy. The second option was to tear down the Viaduct and rebuild it over ten (10) years. During the rebuilding of the Viaduct there would have been limited, if any, north/south access on Highway 99 which would have impacted waterfront jobs and the Port of Seattle’s (“Port”) business. Neither was an acceptable option and that is why in December 2008, the Governor, encouraged by local business and the Port, reconsidered the subsurface (tunnel) alternative. In January 2009 the chosen alternative was to bore a tunnel rather than to convey traffic on the surface.
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