Attention night drivers and late-night commuters: I-5 will see lane and ramp closures from September 15 to 20. The Washington State Department of Transportation (WSDOT) will be installing 17 large girders for a new overpass in DuPont. Some of these beams are up to 156 feet long, with the heaviest weighing 171,000 pounds. As per WSDOT, these structures will connect to the diverging diamond overpass constructed last April, aiming to tie it all into a new roundabout in the area.
For drivers heading south on I-5, especially through DuPont or near Pendleton Avenue at Joint Base Lewis-McChord, expect nightly closures starting September 15. One southbound lane will be closed from 8 p.m. to 4:30 a.m. through September 17. The Center Drive off-ramp to southbound I-5 and the Steilacoom-DuPont Road entrance to southbound I-5 will also be closed during these hours.
On September 18, they're flipping the script and shutting down the I-5's southbound off-ramp to Steilacoom-DuPont Road from 8 p.m. till the early hours of 4:30 a.m. They're handing out a similar treatment on September 19 and 20, with southbound lanes pinched to a single lane opening again at 6 a.m., alongside a closed southbound off-ramp to Steilacoom-DuPont Road pulling an all-nighter until 6:30 a.m. Be wary of intermittent traffic holds afflicting Center Drive and Wilmington Drive, plus the Steilacoom-DuPont Drive roundabout from 9 p.m. to 5 a.m. as crews do their heavy lifting.
Earlier on September 8 and 9, WSDOT crews will install three girders on I-5 at Pendleton Avenue. Pendleton Avenue will be closed nightly from 8 p.m. to 4 a.m., while southbound I-5 will be reduced to a single lane from 10:30 p.m. to 4 a.m. The 41st Division Drive on-ramp to southbound I-5 will also close nightly from 8 p.m. to 4:30 a.m., according to details released by WSDOT.
Patience will be key for drivers traveling through these work zones. WSDOT urges motorists to slow down for safety, plan for delays, and watch out for crews working on site. The new overpass is expected to partially open to eastbound traffic by early 2026, with full completion slated for spring 2026, as part of the I-5 Mounts Road to Steilacoom-DuPont Road Corridor Improvements project.
