Where the Journey Begins’: Inside the $12.7 Billion Gamble to Bring BART to Downtown San Jose

SAN JOSE, Calif. — For decades, the extension of the Bay Area Rapid Transit (BART) system into the heart of San Jose existed only on paper—a theoretical line on a map plagued by funding battles and political skepticism.

But this week, deep in the soil near the San Jose-Santa Clara border, the theory finally turned into concrete.

In a significant milestone for the controversial $12.7 billion Phase II Project, major excavation has officially ramped up at the “West Portal.” This site, located near PayPal Park and San Jose Mineta International Airport, marks the physical beginning of the six-mile extension that will eventually carry trains through a massive single-bore tunnel under downtown.

Here is the investigative status report on the largest infrastructure project in Silicon Valley history.

The Scene: A Gateway in the Ground

The sheer scale of the operation is difficult to overstate. Contractors are currently carving out a “launch structure”—a massive ramp leading to a 133-foot deep pit.

During a media tour on Monday, project officials showcased the heavy machinery required to reinforce this subterranean gateway. Crews are using a 217-foot crane to drop immense rebar cages filled with concrete into the earth, stabilizing the walls that will eventually host the trains.

“We’re rapidly opening up the ground,” said Tom Maguire, Chief Megaprojects Delivery Officer for the Santa Clara Valley Transportation Authority (VTA). “For the first time, folks who have been waiting for this project for decades can start to see where the trains… are actually going to run.”

Sarah Wilson, the project’s construction director, called the site the literal and symbolic start of the line. “This is where the journey begins,” she noted, pointing to the spot where a 53-foot diameter tunnel will eventually plunge 82 feet below the surface.

The Machine: The German Giant is Waiting

While the hole is being dug, the machine that will travel through it is currently sitting in pieces thousands of miles away.

The tunnel boring machine (TBM)—a massive $76 million device custom-assembled in Germany—has completed quality assurance testing. However, it will not be arriving in San Jose immediately.

• The Logistics: The machine is being disassembled for storage and eventual shipping.

• The Delay: Before the TBM can start “chewing through miles of muck,” the launch structure must be finished and major power supplies installed.

• The Timeline: According to Wilson, actual tunneling is not expected to begin until 2028 or 2029. Once started, the boring process will take approximately three-and-a-half years.

The Headwinds: Costs, Contractors, and Trump

Despite the visible progress, the project remains under a cloud of uncertainty. The VTA is navigating a “perfect storm” of logistical and political risks.

1. The Ballooning Budget

Originally estimated in 2014 to cost $4.7 billion with a 2026 completion date, the project has swollen to $12.7 billion with a target completion of 2037.

2. The Contractor Dispute

A significant portion of the current delay stems from VTA’s decision to “offramp”—or part ways—with its main tunneling contractor over cost disputes earlier this year.

• The Impact: Maguire admitted this move could cause up to an 18-month setback.

• The Fix: It remains unclear if VTA will renegotiate with the previous partner or find a new contractor, though Maguire insists there is “global interest” from major firms.

3. The Federal Question

Looming over the financing is the return of President Donald Trump. Local leaders are reportedly weighing whether the new administration might interfere with the federal funding pipeline that is essential for the project’s survival.

The Verdict: Momentum vs. Reality

The VTA’s strategy is clear: dig fast to make the project irreversible.

“We can see progress, and we have momentum, and we need to keep that momentum going,” Maguire urged. The logic is that by completing the launch structure, the agency can shrink the construction timeframe and protect the project from further political or financial erosion.

For the residents of the South Bay, the West Portal site is a tangible sign that the trains are coming. But with a completion date now set for 2037, the question is no longer if they will arrive, but who will still be commuting by the time they do.