Calculated tallies for the design and build bids for State Route 520 bridge have been released by Washington State Department of Transportation (WSDOT). Kiewit-General-Manson’s bid price of US$586.5 million for construction of the new, six-lane floating bridge is US$163.5 million less than the price of US$750 million included in the request for proposals. Kiewit-General-Manson will be supported by engineering firms KPFF and BergerABAM.
WSDOT staff analysed and scored proposals from three prequalified teams vying to design and build the new bridge. Technical scores were combined with bid prices to determine the team with the apparent best value for the project. The other two bidders were Flatiron-Skanska-Traylor and 520 Corridor Constructors, which is made up of Walsh Construction Company, PCL Construction Services and Weeks Marine.
“Replacing the aging SR 520 bridge is a critical priority for the state and an investment that will create jobs today and into the future,” said governor Chris Gregoire. “Identifying the contractor who provides the apparent best value is a major step toward constructing a safer bridge that will keep our economy moving."
WSDOT plans to award and execute this design-build contract in the coming weeks, subject to final review and acceptance of the proposal.
"The bids we opened today show that we can deliver a great transportation project at a great value,” said Washington Transportation Secretary Paula Hammond. “When complete, the new bridge will be safer, better able to withstand winter storms and provide improved commuting options for Puget Sound drivers.” Hammond went on to thank the bidding teams and noted that, “WSDOT appreciates all three teams’ investment in developing their competitive and innovative proposals."
Construction is scheduled to start on Lake Washington in 2012. WSDOT’s goal is to open the new bridge to traffic as soon as December 2014. The design-build contract includes:
- building a six-lane floating bridge with wider, safer shoulders, a transit/high-occupancy vehicle lane in each direction and a bicycle/pedestrian path;
- towing 33 concrete pontoons to be built in Grays Harbor and assembling the floating bridge on Lake Washington;
- building 44 supplemental concrete pontoons and 58 anchors;
- building an east approach connection to the six-lane Eastside highway currently under construction and building a new maintenance facility and dock on the east shore of Lake Washington.
Construction elsewhere on SR 520 is already under way, including improvements on the Eastside and a new pontoon casting basin in Aberdeen. WSDOT expects the first wave of pontoons for the new floating bridge to be towed out of Grays Harbor in 2012. A US$367 million contract was awarded to Kiewit-General in February 2010 for the pontoon project. A US$306 million contract was awarded to Eastside Corridor Constructors in November 2010 for Eastside work.
