(TNS) — California rolled out its vision for high-speed trains between San Jose and San Francisco on Thursday, plotting a 30-or-so-minute ride on what would be one of the busiest stretches of the state’s proposed 520-mile rail system — even as the project is mired in financial uncertainty.

The California High Speed Rail Authority is calling for 220-mph trains, coming from the Central Valley, to merge onto the Caltrain commuter line for a 49-mile jaunt up the Peninsula. Stops would be made at San Jose’s Diridon Station, a new hub in Millbrae and at the Caltrain depot in San Francisco. The San Francisco stop would eventually move to Transbay transit center.

Service between the Bay Area’s largest cities, scheduled to begin in 2031, is expected to take less than 45 minutes, including the stop in Millbrae near San Francisco International Airport. The ticket price is yet to be determined.

The details are part of an environmental review of the Bay Area segment of the ambitious Los Angeles-to-San Francisco project. While the rail authority so far has identified only enough money to build the line through the Central Valley, at a cost of about $20 billion, it’s moving ahead with planning the rest of the estimated $80 billion venture.

“The funding picture always evolves,” said Boris Lipkin, a regional director for the rail authority, in an interview. “We’re taking the steps and doing what we need to do to bring high-speed rail to Northern California.”

Public comment on the environmental impact report for the Bay Area segment is being taken through Aug. 24, and rail officials intend to finalize a plan next year.

Beyond laying out service details, the new document identifies a range of impacts the line will probably have on the area. Figuring out how to run high-speed trains on the densely populated Peninsula was challenging, and rail officials ultimately decided to share existing tracks with Caltrain that roughly parallel Highway 101.

Still, as many as 62 homes and 202 businesses may have to be displaced to upgrade the tracks and build new infrastructure, according to the report. Most of the properties subject to acquisition are in San Jose, San Mateo and Belmont. The Brisbane Fire Station, Millbrae Station Historic Depot and San Jose’s Templo La Hermosa church are among them, the report says.

Once the rail service is up and running, residents of the area also can expect to hear the rumble of more trains and the wail of more horns, the report says.

In anticipation of the project, Caltrain has already started electrifying its tracks to shift from diesel to electric trains that can match the 110-mph speeds the high-speed trains would travel while on the Peninsula.

The two systems will run in close coordination, rail officials say. Faster trains, for example, will be directed to use stretches of track in the rail corridor designed for passing. One of two alternative proposals laid out in the new report calls for several miles of additional passing tracks. That option, though, would come with the greatest expense and the greatest displacement of homes and businesses.

The high-speed trains initially would run twice an hour during peak times, and eventually four times an hour, rail officials say. Because there would be just one stop, it’s expected to be at least 15 minutes faster than Caltrain’s Baby Bullet service.

Service on the segment is scheduled to begin two years after the Bakersfield-to-Merced line, which is expected to start in 2029. The Peninsula stretch will kick off in tandem with the Merced-to-San Jose line, meaning riders will be able to travel from San Francisco to Bakersfield.

The segment south of Bakersfield, to Los Angeles, is scheduled to begin operation in 2033. Trains, at that point, would be able to make the entire journey between Los Angeles and San Francisco, which is scheduled to take two hours and 40 minutes.

The rail line is ultimately planned to continue to San Diego and Sacramento.

High-speed rail has long been a dream of many in California. The project got going in earnest in 2008, when voters approved a bond committing $9 billion to the effort. State and federal funds have since padded the enterprise.

While construction began in 2015 in several Central Valley counties, and continues today, many have raised doubts about the project’s viability. Repeated cost overruns and delays, on top of recent difficulties getting state and federal dollars, have dogged the effort.

The Trump administration canceled a nearly $1 billion federal grant last year, saying the state hadn’t made adequate progress. And this year, the coronavirus pandemic dealt a financial blow to California’s cap-and-trade program — an arrangement in which businesses pay to pollute and the money is channeled to climate-friendly projects like the train.

Republican lawmakers, meanwhile, are joined by some Democrats in calling for the project to be scrapped. They’d prefer the money be spent elsewhere.

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