WSDOT completes anchor cable replacement on the Lake Washington floating bridges
October 26, 2010 · 1:50 PM
Just in time for windy fall weather, crews working for the Washington State Department of Transportation (WSDOT) have replaced 30 worn and corroded anchor cables on the I-90 and SR 520 floating bridges. The thick, steel cables connect the floating bridge pontoons to anchors in the bed of Lake Washington.
Crews replaced 15 of 52 cables on the I-90 Homer Hadley floating bridge and 15 of 58 on the SR 520 floating bridge. The cables, which help the bridges endure strong winds and pounding waves, were nearing the end of their design life. Worn or corroded cables pose a higher risk of snapping during a windstorm, which could lead to a long-term bridge closure.
“Replacing the frayed cables now will make sure the bridges remain safe for drivers this fall and winter and for years to come,” said Ralph Dornsife, WSDOT bridge engineer. “Because these bridges are so valuable to the public, we must make sure they are always in good working order.”
Unlike a typical road project, much of the work to replace the anchor cables took place out of the public eye. Specially-trained commercial deep-sea divers hauled the cables as deep as 200 feet, removed the old cables and attached the new ones. Once each new cable was connected to its anchor on the lake bed, workers fastened them to the floating bridge pontoons.