Last updated December 1, 2016
Building the north portal
Significant construction continues at the SR 99 tunnel’s future north portal. This is the spot where Bertha, the SR 99 tunneling machine, will emerge at the end of her two-mile journey beneath downtown Seattle. As part of this project, Harrison, Thomas and John streets will be reconnected to provide additional east-to-west connections once the tunnel opens.
Below is a rendering of how the future SR 99 will connect to the surrounding surface streets.
Preparing for Bertha and future traffic
Click through the slider below for photos of work happening around the north portal of the tunnel.
The end of Bertha's journey
This photo looks down into the pit where Bertha will complete her journey. The circular outline marks the spot where the machine will break through the wall.
North operations building
Sitting at Thomas Street and 6th Avenue North, the north operations building is nearly complete. It will provide critical management and safety systems for the new tunnel, including ventilation provided by its four distinctive yellow stacks.
The road running underneath the bridge is the northbound lanes exiting the tunnel. The left side will continue on to SR 99 north, while the right side will exit to Republican Street.