WSDOT warns of major weekend closures on I-5, SR 18, I-90

Update: WSDOT announced it is canceling the weekend closure on I-405 in Renton due to equipment issues. 

The Washington State Department of Transportation (WSDOT) is really pouring it on this weekend, as it races to get projects finished before the heavy rainy season arrives. This weekend includes four major projects that will affect drivers in Renton, Kent, Auburn, and Issaquah. WSDOT crews are ready to guide the region through this weekend’s agenda.

Full closure of southbound I-5 in Kent

Starting this Friday at 11:59 p.m., WSDOT will close all lanes of southbound I-5 at SR 516 in Kent. That closure will extend down to S. 272nd Street.

“The reason we’re doing this is that we have 60 broken concrete panels that need to be replaced, and they have a very long cure time, which is why it requires an entire weekend to remove the old panels, place the new panels, and let them cure,” WSDOT spokesperson Kris Olsen said. “This is really vital infrastructure and preservation work to help extend the life of I-5.”

All lanes are scheduled to reopen by 4 a.m. Monday, Sept. 29.

“We are also going to be closing the new Southbound 509 expressway from 24th Avenue to I-5, because otherwise, if people take that, it’s just going to literally dump them into where I-5 closes and takes them off at [SR] 516,” Olsen continued.

SR 18 closure in Auburn, I-90 closure in Issaquah

Additionally, westbound SR 18 in Auburn will have lane, ramp, and directional closures due to replacing the expansion joints on the C Street Southwest bridge.

“We divided into two phases,” David Rasbach, a spokesperson with WSDOT, explained. “The first phase will be from 9 p.m. Friday to 1 a.m. on Sunday. During that phase, we’ll close the right lane of westbound SR 18 and the Auburn Way S. on-ramp to westbound SR 18. At about 2 a.m. on Sunday, we’ll switch to the second phase, and all westbound SR 18 lanes will be closed.”

Phase one will have lane closures between the M and C Streets. Phase two will close all westbound lanes of SR 18 at Auburn Way S.

“Traffic will detour by using the off ramp to Auburn Way S. and then the on ramp back onto westbound SR 18,” Rasbach continued. “This work is important because we’re replacing expansion joints on the C Street southwest bridge. We are telling people to expect delays during busier travel times.”

Lane closures continue through Issaquah on I-90.

“This will begin at 9 p.m. Friday, and will close up to three right lanes of westbound I-90, near Front Street, leaving one lane open,” Rasbach said. “We’ll also close the front street on-ramp to westbound I-90. And this is again to do some bridge work, repairing pavement, and replacing a waterproof membrane.”

All lanes will be open by 8 a.m. on Sunday.

Nate Connors is a traffic reporter for KIRO Newsradio. Follow him on X. Read more of his stories here. Submit news tips here.

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