California high-speed rail officials are considering junking a 2012 decision to build the first segment from Burbank north into the Central Valley — and are now seriously studying the possibility of bringing the first stretch of track north to San Jose instead.

The alternative being examined would run from Silicon Valley to Bakersfield and be less costly than the current proposal to connect the Central Valley with Burbank because it wouldn’t entail expensive tunneling costs, according to a report in the Los Angeles Times.

“This would seriously be a game-changing win,” said Carl Guardino of the Silicon Valley Leadership Group, who also sits on the California Transportation Commission. “One of the big winners would actually be our efforts to electrify Caltrain. High-speed rail comes to San Jose and we electrify Caltrain between San Jose and San Francisco; the winner is everyone who depends on additional speed, with less noise and less pollution.”

The outcome of the new evaluation will be known in the coming weeks, when the state unveils its 2016 business plan. The document will be the most comprehensive update for the $68-billion project in four years.

The first construction started in Fresno in July, 2½ years behind schedule.

If the plan does change, it would be a significant reversal that carries big financial, technical and political impacts, especially in Southern California, where politicians are now stewing over the news.

But a northern route would be a boon for commuters who live in the affordable Central Valley and work in and around San Jose, said former Santa Clara County Supervisor Rod Diridon Sr., who sat on the California High-Speed Rail Authority board until 2010 and strongly supports the bullet train.

“Right now we have 50,000 commuters every day coming north from the Central Valley,” he said. “Highway 152 and I-580 get jampacked, and it’s taking people 2﻿1/2 hours to come from Fresno to work.”

Diridon said the bullet train would clip that commute to 51 minutes and end at the transit hub that bears his name — Diridon Station — with its myriad bus, train and light-rail connections.

But Richard Katz, a longtime Southern California transportation official and former Assembly majority leader, told the Los Angeles Times: “You can’t ignore Southern California or Los Angeles or Orange County and say we are going to go north, period. It made sense to start in the south, given the population and the serious transportation problems here.”

The original decision to start the initial segment in Burbank was considered a major economic benefit to Southern California, providing commuters with 15-minute rides to Palmdale, a connection to a future Las Vegas bullet train and an early link to the growing Central Valley.

But the state is facing major difficulties with the south-first plan. By building in the north initially, the rail authority would delay the most difficult and expensive segment of the project: traversing the geologically complex Tehachapi and San Gabriel mountains with a large system of tunnels and aerial structures.

With the project already behind schedule and facing estimates of higher costs, the Bay Area option could offer a faster, less risky and cheaper option. And getting even a significant portion of the project built early would help its political survival.

When Diridon was on the rail board, the idea was to bring it north to the Bay Area. But he said it became problematic because there wasn’t consensus on what form or path it would take. So the southern option came to the fore.

Now “there may be a window of opportunity to have the San Jose extension be done first,” he said. But that would require a concerted effort and concrete decisions on a subject that concerns residents who live in areas that the tracks would cut through.

“If it ran adjacent to the Union Pacific right of way it can be done quickly and inexpensively,” Diridon said. But that route also cuts through San Jose’s Willow Glen neighborhood, and the people there are “not excited about that,” he added.

An alternative such as a tunnel running between the Tamien and Diridon stations would be more acceptable to residents, but the added costs of putting the tracks underground would likely torpedo the plan, he said.

“We are talking about something that brings great benefits, but also comes with great impacts that no one takes lightly, nor should they,” said Guardino. “The outreach has to be thorough and thoughtful.”

San Jose Mayor Sam Liccardo said he’d heard rumblings that the city may be back in play for the early spur. Still, he said, he’s “not jumping for joy.”

“What would be good for San Jose and Silicon Valley would be to have a completed line that connects the entire state,” he said. “I’m not terribly interested in political battles over whether it gets to one city before another. I’m more interested in either getting it done completely, or focusing those dollars on intercity transit systems like BART.”

Art Leahy, chief executive of the Metrolink commuter rail system in Southern California, said: “I understand they have a difficult political situation, but they really need to come to Los Angeles. … I love the Bay Area, but the economic center of the state is in Southern California.”

Guardino joked that it’s a choice between “Silicon Valley and Silicone Valley.”

“Both of them are centers of innovation,” he said, “but the epicenter of innovation is here, in San Jose and Silicon Valley.”

The Los Angeles Times contributed to this report.