Caught via time-lapse photography, the video below shows the replacement span of I-5 over the Skagit River in Washington State being put into place. Having collapsed earlier in the year, then reopening with a temporary span, the bridge opened to traffic September 15 under the permanent span at around 2 p.m. following what WSDOT describes in this press release as a “carefully choreographed series of activities” beginning the prior day’s evening. Contractors working for WSDOT “used a complex system of hydraulic jacks, Teflon pads and long steel rails to lift and move the two sections of the temporary span onto a work platform for disassembly. Then they used a similar set-up to usher the new, 900-ton concrete span into place.”
WSDOT contractor Max J. Kuney Company worked closely with designer Parsons Brinckerhoff, bridge-mover Omega Morgan and several specialized subcontractors to swap the spans safely, in just 19 hours, and two weeks before the Oct. 1 deadline. Time-lapse video is below.