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3 teams in running to build SR 520 floating bridge project
Three teams have been selected to compete to design and build the new SR 520 floating bridge, estimated to cost $700 million to $900 million. The new bridge will replace the existing vulnerable floating bridge with a six-lane facility that will open to traffic in 2014 and help improve travel between Seattle and Redmond.
The prequalified teams are Skanska-Flatiron-Traylor Joint Venture, SR 520 Corridor Constructors (Walsh Construction Company, PCL Construction Services and Weeks Marine) and Kiewit-General-Manson Joint Venture. The Washington State Department of Transportation (WSDOT) selected these design-build teams based on statements of qualifications submitted in October.
“Recently, we’ve seen how competition – combined with a favorable bidding environment – has driven down costs and increased innovation on many of our projects,” said Paula Hammond, state transportation secretary. “We anticipate these world-class teams will submit competitive bids and provide taxpayers more value for their money.”
In coming weeks, WSDOT plans to issue a request for proposals to the prequalified teams for the floating bridge project. Their bids and proposals will be due in spring 2011. One design-build team will be selected in mid-2011. Construction will begin in 2012 and the new bridge will open in 2014.
This will be the third design-build effort for WSDOT in the SR 520 corridor. Design-build is a type of contract that combines project design and construction together into a single contract. A designer and contractor combine forces to submit a detailed design and construction proposal with a fixed price.
The contract will call for constructing 44 of 77 concrete pontoons needed for the floating bridge, support columns, roadway and new connections at the ends of the floating bridge. A separate contract for the Pontoon Construction Project was awarded in January that will build 33 of 77 concrete pontoons in Grays Harbor for the SR 520 floating bridge.
The design-build contract for a new floating bridge will include:
· Building a new six-lane floating bridge with transit/HOV lanes and a bicycle/pedestrian path.
· Construction of 44 supplemental pontoons and 58 anchors.
· Use of 33 pontoons to be constructed beginning next year in Grays Harbor as part of a contract signed with Kiewit-General Joint Venture.
· Building facilities to treat stormwater from the roadway before it reaches Lake Washington.
· Building a new maintenance facility and dock on the east shore of Lake Washington.
The current floating bridge is vulnerable to windstorms. Stormwater from the bridge currently flows into Lake Washington untreated.