(The Center Square) – Beginning Monday night, contractor crews from Atkinson Construction will begin work of putting into place 30 girders for the construction of two new bridges over Interstate 5 just north of the interchange at State Route 516 in the SeaTac/Des Moines area, the Washington State Department of Transportation announced.
The two new bridges are part of the overall $2.69 billion Puget Sound Gateway Program that is to complete both State Route 167 in northern Pierce County and State Route 509 in southern King County. The overall goal of the project is to complete missing links in Washington’s highway and freight network.
“We hope to make things as seamless as we can,” Kris Olsen, Puget Sound Gateway Program communications manager, told The Center Square about the I-5 project that involves massive girders, some nearly 200 feet long and weighing more than 252,000 pounds. “As far as traffic challenges go, during the overnight shift, we can expect some backups as people approach the work zone.”
Once the girders are in position, one direction of the interstate will be reduced to a single lane overnight and routed to the opposite side of the freeway. No work or closures will happen on weekends or during the day.
On Monday, northbound lane closures are set to begin as early as 7 p.m., with southbound lanes closed about an hour later. From midnight to 4 a.m., one direction of I-5 will be reduced to a single lane of travel using the cross-over lane.
Crews have their work cut out for them.
“A lot of coordination needs to happen between the crane operators in doing what they need to do,” Olsen explained. “Then, the girders need to be up every evening and they will come up on large tractor trailers, where large cranes will pick them up off the truck and set them up. Clearly, there needs to be a lot of coordination.”
The timeline for the project is about a month.
“It’s anticipated that the whole job will take anywhere from 18 to 23 days to complete, and after the northbound lanes are completed we’ll be working on the southbound lanes,” Olsen said.
She expressed excitement about the two new spans – the South 216th bridge and the northbound I-5 flyover ramp – becoming a reality.
“There’s been talk of doing this for two decades now, and right now I would say we’re on schedule to make it happen,” Olsen added.
