Alaska Way Viaduct Replacement Tunnel
Washington State Department of Transportation
The SR 99 Alaskan Way Viaduct was replaced with an approximately two-mile-long double-deck tunnel underneath downtown Seattle. Replacing the viaduct with a tunnel allows the highway to remain open for much of construction, thus minimizing closures and impacts to traffic. Once the tunnel opens, the viaduct will be taken down to clear the way for new public space along Seattle’s downtown waterfront.
DMI was responsible for Plumbing, HVAC, and Track Drainage.
Photo Credits: WADOT