Washington State Department of Transportation

09/23/2025 | Press release | Distributed by Public on 09/23/2025 10:26

Make a game plan: Southbound I-5, southbound I-405 and sections of SR 18 and I-90 close Sept. 26-29

WSDOT asking the public to be aware and plan ahead for extra travel time

KING COUNTY - The University of Washington Huskies will be facing off against the Ohio State University Buckeyes on Saturday, Sept. 27, but crews working for the Washington State Department of Transportation will also be putting on their game faces for region-wide closures beginning Friday, Sept. 26 and continuing through Monday, Sept. 29.

While crews tackle major construction activities in King County, travelers should huddle up to devise their own game strategy. Some of the work is weather dependent so an audible could be called a day or two before the weekend to cancel one or more of the closures.

Here's the starting lineup:

I-5 southbound through Kent

  • Closed from SR 516/Kent Des Moines Road to South 272nd Street.
  • 11:59 p.m. Friday, Sept. 26 - 4 a.m. Monday, Sept. 29.
  • Crews will replace 60 concrete panels and perform other pavement repair work.
  • Detour (PDF 3.4MB): Local traffic can use SR 99 or Military Road South. Southbound SR 167 will remain open for regional traffic.
  • While I-5 is closed, the southbound SR 509 expressway will also close between 24th Avenue South and I-5.

I-405 southbound through Renton

  • Closed from Northeast Sunset Boulevard to SR 167.
  • 11:59 p.m. Friday, Sept. 26 - 4 a.m. Monday, Sept. 29.
  • Crews will install drainage crossings, pave and shift lanes.
  • This work is weather dependent and may be rescheduled if rain is forecast.
  • Detour: Drivers will be directed to a signed detour route via Northeast Sunset Boulevard.
  • This work is part of the I-405/Renton to Bellevue Widening and Express Toll Lanes project.

I-90 westbound through Issaquah

  • Reduced to one lane near Front Street. The Front Street on-ramp to westbound I-90 will also close.
  • 7 p.m. Friday, Sept. 26 - 8 a.m. Sunday, Sept. 28.
  • Crews will perform bridge repair.
  • Work is weather dependent and may be rescheduled if rain is forecast.
  • This work is part of the I-90 westbound SR 900 to East Sunset Way Paving and Expansion Joint Replacement project.

SR 18 westbound in Auburn

  • One lane open 9 p.m. Friday, Sept. 26 - 1 a.m. Sunday, Sept. 28. The Auburn Way South on-ramp to westbound SR 18 closed at the same time. A signed detour will guide people to the Third Street Southwest on-ramp to westbound SR 18.
  • All westbound lanes closed 2 a.m. Sunday, Sept. 28 - 5 a.m. Monday, Sept. 29. All westbound SR 18 traffic must use the off-ramp to Auburn Way South and may use the on-ramp back onto westbound SR 18. Police officers will direct traffic through the intersection.
  • Crews will replace bridge joints.
  • Work is weather dependent and may be rescheduled.
  • This work is part of the eastbound SR 18 C Street Southwest to Green River Paving and Joint Replacement project.

Getting around

Drivers need to plan ahead, allow extra time and expect congestion. People should consider traveling earlier or later in the day to avoid peak travel hours. If possible, reschedule discretionary trips to help reduce backups for those who must travel. Opting to use transit or carpooling will also relieve stress on local and regional detours.

Why the weekend closures are necessary

These closures are part of WSDOT's ongoing efforts to preserve and improve vital infrastructure.

There is never a good weekend for road closures. With a limited season of warm, dry weather, WSDOT must coordinate and plan efficiently to complete work. The number of projects often results in combining weekend closures through the summer and into early fall when the weather starts to become more unpredictable.

Know before you go

While these closures are the go-to plays, they are not the full playbook of all regional roadwork action. Most of the work requires dry weather and the game plan may shift. Travelers are encouraged to check travel times on the Travel Center map, WSDOT mobile app and following the agency's social media accounts.

Washington State Department of Transportation published this content on September 23, 2025, and is solely responsible for the information contained herein. Distributed via Public Technologies (PUBT), unedited and unaltered, on September 23, 2025 at 17:37 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]