Westbound I-90 to close Oct. 20 between Seattle and Mercer Island for tunnel maintenance

Westbound I-90 is set to close overnight on Oct. 20 between Mercer Island and Seattle for scheduled tunnel maintenance.

Lanes will begin closing at 9 p.m. and will fully close by 11 p.m.

The on-ramps from Island Crest Way, 76th Street, and West Mercer Way will all close at 10 p.m.

During the closure crews will perform regularly scheduled maintenance in the Mount Baker and Mercer Lid tunnels.

This work includes fire detection, phone testing, adding an emergency stairwell, and camera cleaning.

Washington State Department of Transportation suggests that travelers use alternate routes around the closure and allow extra travel time.

All lanes are scheduled to reopen on Oct. 21 by 6 a.m.

More information is available through the WSDOT mobile app and the real-time travel map.

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