I-405 directional closures starting this weekend as crews remove temporary falsework structures in preparation for light rail

Work will occur weekends of Aug. 9-12 and 16-19 in Bellevue

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Starting Friday, Sound Transit contractor crews will begin removing falsework, temporary steel columns and beams that were used during construction of the elevated East Link guideway spanning I-405 in Bellevue. To complete this work as quickly and safely as possible, crews will close lanes and ramps on I-405 over two consecutive weekends this month. 

The first closures will be southbound, with northbound closures happening the following weekend.

Southbound: Friday, August 9, 10 p.m. – Monday, August 12, 5 a.m.

  • From Friday at 10 p.m. through Sunday morning at midnight, southbound I-405 ramps in Bellevue will be closed. Traffic will need to use ramp detour routes during this time. 
  • From Sunday morning at midnight through Monday at 5 a.m. southbound mainline lanes will be closed. To minimize impacts to drivers, southbound I-405 traffic will need to use the collector-distributor road at exit 13B as a bypass route during this time. 

Northbound: Friday, August 16, 10 p.m. – Monday, August 19, 5 a.m.

  • From Friday at 10 p.m. through Sunday morning at midnight, northbound I-405 ramps in Bellevue will be closed. Traffic will need to use ramp detour routes during this time. 
  • From Sunday morning at midnight through Monday at 5 a.m. northbound mainline lanes will be closed. To minimize impacts to drivers, northbound I-405 traffic will need to use the collector-distributor road at exit 13B as a bypass route during this time. 

The 810-foot bridge across I-405 will connect the Bellevue Downtown and Wilburton stations when the Blue Line begins operating in 2023. Crews completed the cast-in-place bridge in just over a year. The temporary falsework columns and beams supported the permanent structure while it was under construction.

During the weekend closures, crews will use an electric winch to remove and lower the heavy falsework to the road surface, where it will be completely disassembled and removed. Without the weekend directional closures, this complex process would have taken more than 20 weeks of weeknight work to complete. 

Because these closures will cause traffic backups on I-405, people should plan for extra travel time, and consider alternative ways to reach or travel through Bellevue during these two weekends. Find maps and details about the lane closures at https://www.soundtransit.org/get-to-know-us/news-events/project-updates/upcoming-weekend-directional-closures-coming-to-i-405, and suggested alternate routes from the City of Bellevue at www.BellevueWA.gov/accessbellevue.

East Link extends light rail from the current International District/Chinatown Station to the Eastside with 10 new stations in Judkins Park, Mercer Island, Bellevue and Redmond's Overlake neighborhood. East Link will operate as the Blue Line upon opening in 2023, with trains from the Eastside continuing through downtown Seattle to Capitol Hill, the U District, Roosevelt and Northgate. 
 
Sound Transit is simultaneously working to extend light rail north, south, east and west, opening new stations every few years to form a 116-mile regional system by 2041. The Northgate Link Extension will open as the Red Line in 2021. In 2024, the Blue Line will extend from Overlake into downtown Redmond, along with additional extensions to Shoreline, Mountlake Terrace, Lynnwood, Kent/Des Moines and Federal Way. Further light rail extensions are scheduled to reach West Seattle, Fife and Tacoma in 2030; Ballard in 2035; Paine Field and Everett in 2036; and South Kirkland and Issaquah in 2041.