When the Alaskan Way Viaduct closed, SR 99 no longer ran through the Battery Street Tunnel. As part of the Alaskan Way Viaduct Replacement Program, the Battery Street Tunnel was decommissioned and filled. Filling and sealing the tunnel also provided an opportunity to rebuild and reconnect three streets in South Lake Union – Thomas, John and Harrison – previously cut off by SR 99.
Like the viaduct, the Battery Street Tunnel was built in the 1950s and was seismically vulnerable. Any new or continued use of the tunnel would have required prohibitively expensive renovations. Crushed concrete produced from the viaduct’s demolition was used to fill much of the Battery Street Tunnel, which kept the material out of a landfill. The rest of the tunnel was filled with several types of concrete.
The old northern approach to the Battery Street Tunnel was rebuilt as Seventh Avenue North, an arterial with wider sidewalks, two travel lanes in each direction, transit lanes to help buses get to and from SR 99, and new signalized intersections at John and Thomas streets.
The Battery Street Tunnel was closed to vehicles in February 2019, with final work completed on the project in fall 2021.
Milestone
February 2019
The Battery Street Tunnel closed to all traffic
May 2019
Crews began filling the tunnel with crushed concrete from the demolished Alaskan Way Viaduct
December 2019
Bus lanes opened on the new Seventh Avenue North
Fall 2021
Substantial work was completed on Battery Street and in the area around Seventh Avenue North
Work on the Battery Street Tunnel and North Surface Streets was part of the Alaskan Way Viaduct Replacement Program. The contract that included this work, as well as the demolition of the viaduct and funds associated with rebuilding Alaskan Way along Seattle’s waterfront, cost $366.2 million. Funding comes from state, federal and local sources.
There are no maps or drawings for this project.
This project is one of the 30 projects in the Alaskan Way Viaduct Replacement Program.
The City of Seattle is leading the rebuilding of the new Alaskan Way in the footprint of the old viaduct.
View photos of Battery Street Tunnel work on WSDOT's Flickr page.
Watch videos of Battery Street Tunnel work on WSDOT's YouTube channel.
