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.