By Lynda Myer
Following the City of San Jose approved plans earlier August, early work construction activities will commence soon for San Francisco Bay Area’s rapid transit system phase two extension.
Through an 8km construction underground, the subway line will be extended almost 9.6km from Berryessa Station through downtown San Jose to the City of Santa Clara, by the latest Bay Area Rapid Transit (BART) project.
This project is considered as a part of the wider Santa Clara Valley Transportation Authority’s (VTA‘s) BART Silicon Valley Extension Program, which aims to expand BART services into Santa Clara County. In 2020, phase one of the project has been completed and was inaugurated to the public.
As the BART Silicon Valley II Extension Project, the project’s second phase with US$9.3bn (£7.3bn) value is currently underway and is being billed as the largest single public infrastructure project ever constructed in Santa Clara County.
Benefiting a tunnel boring machine (TBM) an 8km long single bore tunnel is slated to be constructed for this project, whereas it comprises also four new stations at 28th Street/Little Portugal, Downtown San José, Diridon Station and with the end of service in Santa Clara.
The design-build contract for the tunnel and trackwork on the project was awarded to the Kiewit Shea Traylor joint venture (KST) in May 2022.
Following that on 15 August, the City of San Jose approved a final Construction Transportation Management Plan (CTMP), the project is soon expected to progress to the early works construction stage, and it also was granted a CTMP by the City of Santa Clara in June of this year.
The CTMPs permit the VTA transport access and circulation within the station areas during construction.
Moreover, the early works at the West Portal site are planned to start immediately after the approval of the CTMP and associated permits, as it was mentioned in documents published by the KST joint venture in May.
The site grading, which is expected to take five months, and site development, which is expected to take nine months, are the intended early work activities that are scheduled.
Meanwhile, the determined date for construction of the precast plant and TBM segment storage area is the current year, while it will take over than a year and the tunneling process and other construction activities are scheduled to start in spring 2025.
In order to providing general engineering services for the BART Silicon Valley II Extension Project, a joint venture of Mott MacDonald and PGH Wong Engineering won the US$125M (£98.3M) contract in January 2019.
In May 2021, the Federal Transportation Administration calculated that the project could cost an estimated $9.32bn (£7.3bn).
