Caltrans’ $417 million Caldecott Fourth Bore Project, which constructed a two-lane concrete tunnel through a mountain to add to the route’s previous three, reduced congestion for the 160,000 vehicles that utilize State Route 24 passing through Berkeley Hills in Alameda and Contra Costa Counties. The project’s goal was to ease traffic flow on that section of SR 24, one of the San Francisco Bay Area’s heavily traveled roadways. The new tunnel allows for two permanent bores for each direction, rather than reversing the third bore twice a day for traffic. The project was completed $3 million under budget and on schedule and saved commuters 10 to 15 minutes a day, on average.