Plan ahead for Eastside travel: full closure of northbound and southbound I-405 in Renton for drainage work

Closure runs from late Friday, July 12, to early Monday, July 15 

RENTON – Summer is here and so is the summer construction season, including a full closure of northbound and southbound Interstate 405 in Renton starting at 11 p.m., Friday, July 12, to 4 a.m., Monday, July 15.

Contractor crews working for the Washington State Department of Transportation will shift traffic, demolish the existing 112th Avenue Southeast bridge at Exit 9 and install drainage crossings under the north and southbound lanes of I-405 during the closure. This work is part of the I-405/Renton to Bellevue Widening and Express Toll Lanes Project.

Detour routes cannot accommodate normal I-405 traffic volume, so travelers are advised to plan ahead, travel during off-peak hours or, if possible, delay discretionary travel to help minimize the backups.

I-405 closure details

During the closure:

  • Northbound I-405 will be closed from the North Southport Drive on-ramp to I-405 to the I-405 off-ramp to 112th Avenue Southeast.
  • Southbound I-405 will be closed from Coal Creek Parkway Southeast on-ramp to I-405 to the I-405 off-ramp to Northeast 30th Street.
  • Signed detour routes will guide people around the I-405 closures in both directions.

People should also note all lanes on eastbound I-90 from Seattle to Mercer Island will be closed beginning at 10 p.m. Friday, July 12, until 6 a.m. Saturday, July 13, for tunnel maintenance. The southbound I-5 off-ramp to eastbound I-90 and the northbound and southbound Rainier Avenue South on-ramps to eastbound I-90 will close starting at 9 p.m. Friday, July 12. All lanes and ramps will reopen by 6 a.m. Saturday, July 13. 

Schedule updates will be available on the project webpage, WSDOT’s Travel Center map, the WSDOT mobile app and by signing up for King County email updates.

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