SR-99 Tunnel North Access Connection
The Washington State Department of Transportation awarded a $41.6 million contract to Guy F. Atkinson Construction for the SR-99 Tunnel North Access Connection project.
As part of the Alaskan Way Viaduct replacement program, the Atkinson team will construct the SR-99 tunnel’s north access entrance and exit roadways from the portal structure at Harrison Street to north of the Mercer Street bridge. The team also will build on- and off-ramps at Republican and Harrison streets and extend Sixth Avenue North from Harrison Street to Mercer Street.
Once the new roadways and bridges are complete, the team will demolish the existing SR-99 bridge over Broad Street. As part of their scope, the team also will install traffic signal, illumination, and ITS systems, and relocate existing utilities, including water, storm, sewer, and high voltage electrical systems.