Local Information

World’s longest floating bridge gets in the swing with giant hinge

Tuesday, April 21, 2015 - 14:53

Ian Sterling, WSDOT communications, 206-819-7230

Installation of transition span underway on east side of Lake Washington

MEDINA – The new State Route 520 floating bridge will get a critical component this week. Contractor crews for the Washington State Department of Transportation today began to install a massive, hinged transition span that acts as a threshold between the highway’s floating roadway and its stationary, elevated segment near Lake Washington’s eastern shore.

Crews expect to have the transition span fully in place by Thursday, April 23. Eight massive girders make up the span. Each girder is 190 feet long and weighs 45 tons.

The giant span operates somewhat like a hinge on a door. It moves along with the floating bridge while connecting it to the highway’s stationary east high-rise—serving as a transition between the two structures. The span will support the new bridge’s westbound lanes and a bike/pedestrian path at the east end of the new floating bridge. A smaller hinged span for the eastbound lanes was installed last June. Similar spans will also be installed at the west end of the floating bridge prior to its opening in the spring of 2016.

WSDOT reminds drivers to be cautious near the work site; the installation process, employing a large derrick crane, could be a visual distraction. Drivers approaching the construction site from the existing SR 520 floating bridge should pay extra attention to driving conditions and the road in front of them, and be mindful that other drivers could slow down or brake as they pass the construction site.

The installation is one of many milestones for the SR 520 Bridge Replacement and HOV Program. All of the new bridge’s 77 pontoons are now constructed and on Lake Washington. Joined and anchored pontoons now stretch well over halfway across the lake, and work continues in Seattle on the West Approach Bridge North Project.

For information on road closures associated with SR 520 construction, please visit the SR 520 Orange Page and follow us on Twitter.

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