We have been keeping track of California’s bullet train boondoggle, or as some call it, a “Browndoggle” after governor Jerry Brown. He backs the train and wants to dig two massive tunnels under the Sacramento-San Joaquin River Delta at an estimated cost of $25 billion. Now taxpayers learn that the bullet train also has a problem with tunnel vision.

As Ralph Vartabedian notes in the Los Angeles Times, “the monumental task of building California’s bullet train will require punching 36 miles of tunnels through the geologically complex mountains north of Los Angeles.” This entails crossing the tectonic boundary between the North American and Pacific plates, plus unmapped earthquake faults. “It will be the most ambitious tunneling project in the nation’s history,” Vartabedian writes, but the California High Speed Rail Authority “hasn’t yet chosen an exact route through the mountains” and is “behind schedule on land acquisition, financing and permit approvals, among other crucial tasks, and is facing multiple lawsuits.”

The reporter cited expert James Monsees that the tunneling project is not realistic and that faults cause trouble. Bent Flyvbjerg of Oxford University, an expert on megaproject risk, told the Times, “You have an 80% to 90% probability of a cost overrun on a project like this.” Robert Bea of the National Academy of Engineering told the reporter “you can never make up an early cost increase,” and the bullet train has already had such increases. As Vartabedian explains, “at $68 billion, the budget is already more than double the $33-billion estimate made by the rail authority before California voters approved bonds for the project seven years ago.” By one estimate, the first phase from Burbank to Merced had risen 31% to $40 billion.

Add the most ambitious tunneling project in U.S. history and the bullet train is certain to cost many times the $68 billion budget. Even if it manages to go from Los Angeles to the Bay Area, as advertised, the bullet train will be slower than air travel and doubtless more expensive. For taxpayers it’s a boondoggle at any speed.