The 9.6km, four station extension, which will take the service through downtown San Jose and into Santa Clara, was originally priced at US$9.3bn and scheduled to open in 2030.

The VTA board has now established an ad hoc committee to ensure the project is delivered efficiently and quickly.

“We are doing everything possible as responsible stewards of taxpayer monies to maintain costs at every stage. We will continue to do so in the face of inflationary pressures and hikes in interest rates,” said general manager and CEO Carolyn Gonot. 

VTA said the revised cost and schedule reflected the project’s progress, additional funds for risk and contingencies and major changes in market conditions since the last cost estimate in 2020.

The project cost has been affected by higher labour, material and equipment prices; higher interest rates; material shortages; lack of competition; the current contracting environment; and the Covid-19 pandemic.

VTA said the increased estimate also reflected the project’s progress over the last two years, including the advanced design, award of the tunnel and trackwork contract, and contractor-proposed design innovations. These changes include: 

  • a larger diameter tunnel to accommodate parallel tracks with a single centre platform
  • elimination of the mid-tunnel facilities 
  • reconfiguration of the 28th Street/Little Portugal BART Station
  • refinements to the Downtown San José BART Station design to improve access and circulation
  • accommodation for future entrances at Downtown San José and Diridon BART Stations 

The revised schedule reflects new dates to bring on contractors to complete construction, additional time to test the system prior to opening, longer construction duration, and contingencies at key project milestones based on lessons learned and the regulatory environment.

The VTA said early construction activities were still planned to start in each station area in 2024. 

VTA is also refining the project’s contract delivery strategy for the remaining contracts, moving away from the design-build model towards the more traditional design-bid-build model.

In May last year a Kiewit Shea Traylor joint venture was awarded the US$235m progressive design build contract for the tunnel and trackwork.

Initially it was envisaged the single-bore tunnel would be a two-level construction but Kiewit Shea Traylor proposed the two tracks run parallel. The configuration is expected to be cheaper to construct, easier to maintain, make access more efficient and provide better ventilation.