Less than four years after groundbreaking, the Caldecott Fourth Bore will soon open to traffic. The new tunnel will join three existing tunnels on the busy State Road 24, which connects Contra Costa and Alameda counties through the Berkeley Hills of northern California’s San Francisco East Bay Area. The 3,389-foot (1,033-meter) long tunnel was constructed using Sequential Excavation Method / New Austrian Tunneling Method (SEM / NATM) techniques, and was completed under budget. A Ribbon Cutting Ceremony will take place this Friday, November 15 at the tunnel’s East Portal in Contra Costa County to celebrate the completion of the Caldecott Fourth Bore. For more information on this project, please visit GZ’s Caldecott Tunnel Fourth Bore project page.