DUPONT, Wash. — This story initially appeared on MyNorthwest.com
The birth of a new freeway interchange; it’s happening this weekend on Interstate 5 (I-5) in DuPont, but it will come with a price for drivers.
The new Steilacoom-DuPont Road interchange is taking shape, just north of the original, on I-5. This weekend, the contractor is installing 13 massive girders over the freeway that will serve as the new overpass.
“These 200,000-pound girders, a total of 13,200,000 pounds each, has to be picked up from trucks and then placed up above where they will rest and provide the new overpass backbone,” Doug Adamson, assistant communications manager with the Washington State Department of Transportation (WSDOT), said.
The contractor needs to close the freeway, both Friday night and Saturday night, to make this happen.
“This is for safety,” Adamson said. “These are huge pieces of steel and concrete that we’re suspending in mid air above the active lanes of I-5. That’s why we can’t have people in the area at that time.”
What will the closures look like?
All traffic will be diverted off the freeway during these nighttime closures.
“We’ll begin lane closures northbound and southbound I-5 at 8 p.m., but at 10 p.m., we’ll divert all of I-5, both north and southbound lanes, through the exit and the on ramp at Steliacoom-DuPont Road,” Adamson said.
Even though these closures are happening overnight, Adamson said they have the potential to create extended delays.
“We will keep traffic moving, but it’s not going to be easy,” Adamson said. “Everyone is going to go through the exit and the on ramp, both northbound and southbound I-5, and while we do this, we anticipate miles-long backups.”
WSDOT is building this new interchange to accommodate all the growth at Joint Base Lewis–McChord (JBLM) and the surrounding communities. It will also get rid of the train trouble at the current off-ramp. There is an at-grade crossing just off the freeway. This new overpass will go over the tracks.
“This new overpass replaces one that was built in 1957, and it is rated in poor condition,” Adamson said. “It doesn’t meet our current earthquake standards.”
This project also includes extending the HOV lane from where it ends near this interchange to Mounts Road. The old overpass will also be taken down.
“We are anticipating to have everything buttoned up and done by the fall of next year,” Adamson said.
The overnight lane closures are scheduled for the next two weekends.
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