Weekend-long directional closures of the Interstate 90 outer roadways resume starting the weekend of Oct. 9-12. Four more weekend-long directional closures are scheduled to be completed before the end of 2015.

The closures will allow contractor crews working for the Washington State Department of Transportation and Sound Transit to continue upgrading the operations systems inside the Mount Baker tunnel and Mercer Island lid. The work also sets the stage for light rail service across I-90.

During the weekend-long closure, all westbound traffic between Bellevue Way and Rainier Avenue South will be reduced to one lane and detoured into the I-90 express lanes.

The majority of the work takes place inside the tunnels and out of the view of drivers. However, there will be a few noticeable changes made following the previous westbound I-90 detours this spring, including two lanes exiting the express lanes in Seattle to help keep traffic moving through the work zone. Mercer Island drivers will continue to exit at East Mercer Way, but will now have the option to use East Mercer Way or Island Crest Way to reach the island.

Closure details

Friday, Oct. 9 – Monday, Oct. 12

• Contractor crews will shift all westbound I-90 traffic between Bellevue Way and Rainier Avenue South to the express lanes from 11 p.m. Friday to 5 a.m. Monday.
• Drivers wishing to access Mercer Island will need to exit westbound I-90 at East Mercer Way. There are no westbound exits to Mercer Island from the express lanes.
• Those traveling from Mercer Island to Seattle should enter the express lanes at 77th Avenue Southeast or Island Crest Way.
• Westbound I-90 drivers will be unable to exit to Rainier Avenue South and should follow the signed detour using Fourth Avenue South and eastbound I-90.
• Drivers transporting flammable materials westbound across Lake Washington must use alternate routes such as Interstate 405, State Route 520 or State Route 522.
• The I-90 Trail will not be impacted during the closure.

What’s next

There are 24 more weekend directional closures of I-90 planned between now and mid-2017. These closures are part of the I-90 Two-Way Transit and HOV Operations project, which preserves the three general purpose lanes while adding all-day carpool lanes to I-90 and direct access ramps for transit, carpools and vanpools.

In mid-2017, Sound Transit contractors will begin work on the I-90 express lanes to operate exclusively for light rail as part of the East Link light rail project. The 14-mile East Link project, set to open in 2023, includes 10 new stations connecting Seattle, Mercer Island, Bellevue and Overlake.