Both directions of the State Route 99 tunnel in Seattle will close for scheduled maintenance beginning at 10 p.m. Friday, Oct. 6, until 6 a.m. Saturday, Oct. 7, according to a news release.
The tunnel closure will allow the Washington State Department of Transportation an opportunity for several important tasks, including:
The Bridge Preservation Office will perform structural inspections.
Signals and electrician crews will conduct lighting repairs, camera cleaning and sign maintenance.
Maintenance crews also will inspect fire extinguishers, deluge cabinet heaters and fire sprinkler heads, test fire deluge valves, replace fire and phone signs, calibrate the haze detector, and replace the jet fan differential sensor.
People traveling through downtown Seattle Friday night should use alternate routes.