Caldecott Tunnel Fourth Bore

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On Friday, November 15, 2013, CCTA and project partners Caltrans, Metropolitan Transportation Commission, and Alameda County Transportation Commission cut the ribbon on the Caldecott Fourth Bore, signifying the successful completion of a monumental engineering feat – and the long-awaited start of smoother traffic flow along a critical corridor for 160,000 motorists each day.

At the time of the groundbreaking on January 22, 2010, the shovel-ready Fourth Bore was the largest transportation project to receive federal Stimulus funding. The Fourth Bore project had been years in the making and was completed on time and under budget at a cost of $417 million. Since the ribbon cutting, the Fourth Bore has improved mobility for motorists and emergency crews; reduced delays and improved travel times; eliminated the need for daily tunnel reversals and lane merges; and enhanced safety of the traveling public and Caltrans maintenance workers. The Fourth Bore represents what is possible when communities, public agencies, and individuals join one another in partnership toward a shared goal.


We wish to commemorate Tunnel Designer Bhaskar Thapa who passed away just a few months before the Fourth Bore opened to traffic – and just prior to his 50th birthday. For many years, Bhaskar worked tirelessly alongside numerous others to ensure the vision of the tunnel would become reality.


In memory of Tunnel Designer Bhaskar Thapa