The Washington State Department of Transportation (WSDOT) and Kiewit-General (K-G) floated the first new State Route 104 Hood Canal Bridge pontoons out of the Tacoma Concrete Technology graving dock early Wednesday morning. Fifteen feet of water filled the graving dock, lifting up the 6,000+ ton structures. Tugboats then towed the pontoons out of the graving dock and moored them in Blair Waterway. Over the next week, crews will prepare the pontoons for their 35-mile journey to Seattle.
"This accomplishment is another step toward providing drivers with a bridge that is wider, safer and more affordable to maintain," said Eric Soderquist, project director. "Completing these pontoons is an important project milestone leading up to the May/June 2009 bridge closure and replacement."
WSDOT and K-G lead the world in floating bridge technology. Construction of the first three of 14 Hood Canal Bridge pontoons was completed in nine months. The team successfully worked its way through a variety of engineering challenges to deliver these pontoons. Good planning and continuous improvement in work techniques contributed to the work being done earlier than anticipated, giving the project a little extra time in the future to handle unexpected challenges should they arise.
WSDOT and K-G will construct 14 new pontoons inside the Concrete Technology graving dock in four cycles. Three pontoons were built in this first cycle. Five pontoons will be constructed in the second cycle, four pontoons in the third cycle and two pontoons in the fourth cycle.
Another three pontoons, built during the west-half bridge replacement in the early 1980s, will be towed from Port Gamble Bay to Seattle in early January to be retrofitted. The completed east-half pontoon roadway sections and fully assembled east-half draw span will be floated into place during the bridge closure in May/June 2009.
The Hood Canal Bridge is the longest floating bridge over saltwater in the world.