Tunnel vision on BART extension?
Some transit advocates urge VTA officials to reevaluate decision to use single-bore method
After a recent federal report projected that BART'S extension into downtown San Jose would blow past the anticipated opening date and price projections, new questions are being raised about local transit officials' plans to build one of the nation's largest subway tunnels.
At the center of the debate is a decision made by the Santa Clara Valley Transportation Authority and BART in 2018 to reject a more standard tunneling method known as twin-bore, which would create shallower stations but also require tearing up sections of Santa Clara Street for years at a time. Instead, officials chose to pursue an innovative subway building technique known as single-bore, which will reduce disruptions at ground level by building a larger single tunnel and placing BART stations deeper underground.
For months, VTA leaders and San Jose Mayor Sam Liccardo, who is also a VTA board member, have claimed that the extension was approved for federal funding because of this unique tunneling method and that redesigning the project could jeopardize up to $2.3 billion in federal funding by forcing the agency to reapply for assistance.
“The very commitment of federal dollars depends upon the deployment of that innovative single-bore design, so anyone who wants to propose something different should also figure out where an additional $2 billion will come from,” Liccardo said in a recent interview.
But new statements released to this news organization by the Federal Transit Administration refute that narrative.
“VTA reviewing the tunneling method does not affect FTA'S
discretion to fund the project,” a spokesperson for the FTA wrote in an email. “… (C)hanging the bore method would not require VTA to resubmit plans to FTA or go through the funding approval process again.”
VTA officials said this was new information to them. Still, they claim that reverting to the original twin-bore design would tack three years onto their timeline because the agency would have to update project plans to meet the latest construction and safety codes, reopen a complicated state and federal environmental clearance process and rebid the project.
“We're talking thousands of drawings,” VTA'S BART Program Chief Takis Salpeas said in an interview. “We're not talking about small stuff.”
The FTA confirmed that a change in design would need to go through the federal environmental review process known as NEPA, which Liccardo said is “not a small detail.”
“Every year of delay adds tremendously to the cost, and with a
project of this size that's hundreds of millions of dollars,” he said.
The 6-mile, four-station BART extension, managed by the VTA, is slated to be the largest infrastructure project in Santa Clara County history. The project, which is being built by VTA but will be operated by BART, was approved by nearly 71% of Santa Clara County voters in 2000. Since then, voters have approved two sales tax measures that together will provide about $4 billion for the extension.
Despite this support for the project, the extension's underground tunnel design has been a controversial topic for years. The single-bore technology has never been used to mine a subway tunnel in the United States, and a Seattle highway project that used single-bore was mired in delays.
Recently, critics have argued that VTA is compromising the convenience of riders to avoid a few years of inconvenience to businesses downtown. Under the single-bore design, riders will be required to descend as far as 90 feet to get from the street to their
trains, and they will only be able to enter and exit the downtown San Jose stations on the north side of Santa Clara Street. Also, critics say, high-rise development will be more difficult to construct above the stations than with the twin-bore method.
VTA staff originally said the single-tunnel design would save time and money, with trains running through downtown San Jose by 2026. But the recent federal analysis called the timeline for the project “overly ambitious” given the “very challenging” work of building a single large-diameter tunnel of this scope. The FTA analysis predicts the extension will be finished as late as 2034 and cost $9.1 billion, nearly double the first estimate.
In light of the new analysis, some Bay Area transit advocates are urging VTA to reevaluate the design.
“We want to make sure the project is worth the wait and worth every penny,” said Laura Tolkoff, transportation policy director at SPUR.
Some on the BART board say they now regret the decision to approve the design. “I would jump for joy if they decided to abandon the single bore,” said Robert Raburn, who voted for it.
BART Director Liz Ames, who joined the board after the project design had already been approved, has been asking the VTA to conduct a new cost comparison of the two tunneling methodologies since 2019. “To me, this is about public trust,” she said.
Both methods were analyzed under the state's environmental impact law known as CEQA. The twin-bore design plans were 65% complete when the boards voted to make the switch, and the single-bore designs are now about 35% complete.
Megan Jennings, an attorney at Coblentz Law who specializes in CEQA, said that it is feasible it could take the VTA three years to complete the environmental and design tasks needed to make the switch, as the agency has suggested, but it wouldn't necessarily have to take that long.
“CEQA does not always require that you go back to the drawing board and start your analysis from scratch,” she said. “If this isn't really a significant change from what was approved in 2018, potentially it could be a much simpler path.”
Although VTA officials oppose a redesign of the project, other agencies have taken this route without a loss in federal funding.
In Boston, for instance, local transit agencies redesigned a long-anticipated extension of a popular light rail route there — known as the Green Line — following revelations the project was going to cost $1 billion more than the anticipated estimate. The federal government deemed the updated project was still within the same project parameters and eligible for funding.
But local leaders are unpersuaded.
“Unless someone can really demonstrate that dual bore is safer and/or cheaper and/or faster, it makes little sense to be pulling back,” Liccardo said.