This coming weekend, on October 10 – 11, Seattle Department of Transportation and Washington State Department of Transportation crews will work overnight on the Battery Street Tunnel fire suppression system. In order to accomplish the maintenance work, the southbound tunnel must be closed from 10 p.m. Saturday until 6 a.m. Sunday morning.
During the closure, traffic heading southbound on SR99/Aurora Avenue N will be detoured just before the tunnel onto the Denny Street exit; from Denny, traffic will be directed west on Wall Street onto Elliott Avenue and then back onto SR 99/ the Alaskan Way Viaduct via the southbound Elliott Avenue on ramp. Motorists should allow for the additional time to follow the detour. The tunnel northbound will remain open to traffic.