Santa Clara VTA Board amends tunnel and trackwork contract for BART Silicon Valley Phase II Project
The Santa Clara Valley Transportation Authority (VTA) Board of Directors has authorized an amendment to the Kiewit Shea Traylor Joint Venture’s (KST) tunnel and trackwork contract (CP2) for the Bay Area Rapid Transit (BART) Silicon Valley Phase II Project. The amendment facilitates preparatory efforts and construction of the large shaft structure from which the tunnel boring machine (TBM) will be launched. Santa Clara VTA notes that beginning construction of the TBM launch structure is a critical step to maintain the project’s estimate and schedule of 2037 passenger service date.
The value of the newly authorized KST amendment, not to exceed $366.4 million, reflects a $15 million negotiated reduction from the contractor's last estimate. Santa Clara VTA notes construction of the launch shaft will be executed concurrently with the custom manufacturing of the TBM, which is already underway, ensuring site readiness to tunnel boring in 2027.
“When we put our shovel in the ground in February, we’ll be taking the biggest step yet toward building our five-mile tunnel,” said Santa Clara VTA Chief Megaproject Officer Tom Maguire.
The agency notes CP2 is being executed in two stages and the current work is part of the first stage authorized by the board in May 2022. Other work in the first phase includes investigation of cost saving and delivery innovations, programming and design services, procurement of the TBM, demolition, utility relocations and other early site and general preparatory and construction activities.
Stage 2 of CP2 would be for all remaining tunnel related work, including construction of the tunnel, concrete structures in the tunnel, portals, station shafts and tunnel connections, underground boarding platforms and trackwork. Santa Clara VTA notes a decision and suggested path forward on Stage 2 will be shared in the first quarter of 2025.
On June 12, 2024, Santa Clara VTA broke ground at the site of the future Santa Clara Station, which will include the station, rail and maintenance yard and tunnel’s west portal where the TBM will be launched from and where passenger trains will descend to or ascend from the five-mile tunnel. To date, the agency notes work at the site has included site grading, drainage, utility relocations, constructing on-site access points, crew parking and offices and construction fencing while upcoming work includes installing a noise curtain to protect nearby residents and businesses, building the launch shaft, constructing a tunnel liner factory and storage area, excavated material bin and a grout plant to make the sealant for tunnel liners.
The extension of the regional BART system is the largest transportation infrastructure project in the history of Santa Clara County, Calif. The project will integrate Santa Clara County with the greater Bay Area BART system, enhancing regional connectivity and providing numerous economic, environmental and social benefits.
