All traffic heading to Seattle on westbound Interstate 90 Saturday night and Sunday morning will use the reversible express lanes in the center roadway of I-90. During the closure crews will test the ventilation system in the Mount Baker Tunnel.
At 11:30 p.m. Saturday, Oct. 22, crews working for the Washington State Department of Transportation will close the mainline of westbound I-90 at the East Channel Bridge in Bellevue and reroute westbound traffic to the express lanes. All lanes will remain open west of the Mount Baker Tunnel in Seattle. Westbound mainline I-90 east of the tunnel will reopen to all traffic and the express lanes will resume eastbound by 8 a.m. Sunday.
The work is part of the I-90 Two-Way Transit and HOV Operations project, which is adding an additional HOV lane in each direction of mainline I-90 between Bellevue and Seattle. In preparation for upgrades to the tunnel’s fire-safety system, engineers will measure the current capacity of the ventilation system to determine what improvements are necessary for an added HOV lane to carry more vehicles through the Mount Baker Tunnel in 2015.