VTA's BART extension construction underway amid delays, funding gaps

SAN JOSE, Calif. (KGO) -- Crews are working nearly 24/7 on the early phases of VTA's BART extension in Santa Clara County.

The project will extend public transportation from the existing station in North San Jose, through downtown and to the city of Santa Clara.

"The project is the largest infrastructure project ever undertaken in Santa Clara County," VTA's chief megaprojects delivery officer Tom Maguire said. "It will, when finished, involve six miles of new rail, a five-mile, single-bore tunnel and four new stations."

Work on phase two is already underway.

We got a firsthand look of the construction at the west portal where the Santa Clara station will be - just behind PayPal Park.

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Crews are preparing the site and laying the foundation for the starting point of the tunnel and there's a lot of loud work going on.

Sound walls surrounding the area are actually a key part of this project.

Construction happens from 6 a.m. to 4 a.m. Monday thru Saturday and these walls make it so there are limited disruptions overnight for the houses just on the other side.

The west portal is also where the dig for the tunnel will begin.

Due to the type of soil in the ground here, crews are building and installing the walls of the tunnel first.

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"The walls go top-down," VTA's director of construction Sarah Wilson said. "The walls get completely installed before we excavate anything. We're going to dig down 82 feet and it will be a nice big opening for our mega-machine to launch their and build a tunnel."

The tunnel will be bored by a new contractor after bids came in way over budget.

The federal government committed $5.1 billion to pay for nearly 40% of the project. But there is still a funding gap of somewhere around $700 million to $1 billion.

So, VTA has to find creative and cost-effective ways to get the job done.

"Our challenge now is to find a way to build the tunnel faster and to build the other aspects of the project - the four stations, the yard and all the construction above ground - in a way that compresses the schedule," Maguire said.

VTA and BART are still eyeing a 2037 completion of the project to get trains up and running for the community in the South Bay and beyond.