Abbi Russell, WSDOT communications, 360-905-2058
MENLO – Drivers on the State Route 6 Willapa River Bridge will get a front-row seat next week for a major milestone on a new bridge under construction just 12 feet away from the one they’re crossing.
On Nov. 11 and 12, crews with Washington State Department of Transportation contractor Rotschy Inc. will set 12 concrete girders for the new bridge spanning the river. The new structure replaces the aging steel-truss bridge drivers have used since 1929.
The girders – ranging from 75 to 125 feet long – are prefabricated in Tacoma and delivered to the construction site, ready to set. Crews will use a crane to place each girder on the piers they’ve been building since August. The new bridge has three spans, each of which takes four girders to complete.
Once the girders are set and secured, crews will work during the winter to build the 275-foot-long bridge deck. They will first build a wooden support structure around the deck, then place and tie together mats of steel rebar and pour concrete to form the driving surface.
The concrete will take several weeks to dry and harden, a process called “curing.” Once curing is underway, workers will build other features of the bridge, such as concrete barrier and bridge railing. They will also construct new bridge approaches and prepare to realign SR 6 so the existing highway ties into the new structure.
WSDOT expects to open the new bridge to drivers and demolish the old bridge by fall 2014.
WSDOT is replacing the existing Willapa River Bridge with a wider, more modern structure. The new 36-foot-wide bridge will better meet the needs of today’s drivers and help improve traffic flow on this key connection between Interstate 5 and coastal communities.
The $6.3 million project is funded by the 2005 gas tax and other state highway-improvement funds.