Caldecott Tunnel Fourth Bore
Client: California Department of Transportation (Caltrans) / Contra Costa Transportation Authority (CCTA)
Location: Oakland & Orinda, California
Project Value: Approximately $417 Million
Market: Transit & Transportation
Services: Construction Management, Construction Inspection, Resident Engineering, Quality Assurance
Key Features: Fourth highway tunnel bore, approximately 3,400-foot tunnel, seven cross passages, ventilation systems, intelligent transportation systems, seismic improvements, and traffic operations enhancements.
The Caldecott Tunnel Fourth Bore Project expanded capacity along State Route 24 by constructing a new two-lane tunnel beneath the Berkeley Hills, improving one of the Bay Area's busiest commuter corridors connecting Alameda and Contra Costa counties. Completed in 2013, the project eliminated the need for daily lane reversals, reduced congestion, enhanced emergency response access, and improved overall safety for more than 160,000 motorists using the corridor each day.
The project included construction of a new highway tunnel, cross passages connecting the new and existing bores, roadway improvements, mechanical and electrical systems, ventilation facilities, and advanced traffic management systems. Built using sequential excavation methods, the Fourth Bore significantly improved mobility while providing a safer and more resilient transportation corridor for the region.
EPC provided construction management support throughout project delivery, assisting with construction oversight, contractor coordination, quality assurance, field engineering, and project documentation. Working closely with Caltrans and project partners, EPC supported the successful delivery of this nationally recognized transportation improvement while maintaining safety, quality, and schedule objectives.