The Washington State Dept. of Transportation is creating a list of best construction practices for floating bridges, based on results of tests conducted on a pontoon built at one-sixth the typical size. The best practices will be used by the design-build team that won the contract to build new pontoons for the state Route 520 Evergreen Point Floating Bridge. At 2,285 meters, SR 520's bridge is the longest of its kind in the world.
WSDOT and its contractor, Aberdeen, Wash.-based Quigg Bros. Inc., last month wrapped up the $2.8-million "Advanced Construction Methods and Engineering for Pontoons" project, which comprises 11 stages of pontoon construction, says Scott Ireland, WSDOT project engineer. "We learned a tremendous amount, and our lessons learned exceeded our expectations," Ireland says.