SR 99 double-deck tunnel in Washington opens to traffic


The Washington State Department of Transportation (WSDOT) has announced the opening of the new SR 99 tunnel, a two-mile, double-deck tunnel part of replacement for Seattle’s seismically vulnerable Alaskan Way Viaduct, to traffic.

The tunnel’s northbound lanes have been opened to vehicular traffic and all ramps to and from the tunnel were open to drivers.

However, the new northbound off-ramp to South Dearborn Street, near the stadiums, will take another one to two weeks to be completed.

Washington Governor Jay Inslee said: “Today, we can say we’ve forged a new path. From Jimi Hendrix to Bertha Knight Landes, our state’s history is filled with examples of ingenuity and perseverance.

“The opening of this tunnel is further proof that we can overcome big challenges and create lasting change in our communities.”

The tunnel will provide travellers a direct route under downtown with new entrances and exits at each of the tunnel portals located at the north and south ends of downtown.

Transportation Secretary Roger Millar said: “This is a game changer. Our number one goal was to remove a vulnerable structure from our highway system.

“Along the way we reshaped a major transportation corridor that is a key component of the multimodal transportation system we and our partners are building for the Puget Sound region.”

Until the new northbound ramp opens, the last exit for travellers on northbound SR 99 before the tunnel will be at South Spokane Street and the next available exit will be at the north portal, near Seattle Center.

Buses that used to travel on the viaduct will continue their reroute until the ramp opens.

Millar said that the WSDOT will continue to coordinate with partner agencies to monitor traffic conditions and make adjustments as needed.

He said: “People really stepped up and did their part during this closure. We’re hoping that people discovered new ways to get around over these past few weeks, and that they’ll be willing to keep it up.

“When more people make smart commuting choices, it makes it easier for all of us.”

Tolling could begin in summer 2019 and toll rates will range from $1 to $2.25 with a ‘Good To Go!’ pass, depending on time of day.


Image: The SR 99 Tunnel in Seattle. Photo: Courtesy of WSDOT/flickr.

With 11 websites and newsletters covering all the key areas within the construction industry, World Construction Industry Network is the leading global construction information resource. READ ABOUT US



World Construction Network | is a product of GlobalData. Copyright © 2022 GlobalData. All rights reserved.