The high-speed rail expansion connecting the Caltrain station at Fourth and King streets to the Salesforce Transit Center just got a major boost, as the Federal Transit Administration just kicked down $3.4 billion to make the project a reality.

We noted in our photoset of Sunday’s Bay to Breakers this morning that as seen below, a handful of jokers made themselves into a cardboard Caltrain to spend the day partying and celebrating on the streets.

Image: Joe Kukura, SFist

But officials at Caltrain may have spent the weekend partying and celebrating too. NBC Bay Area reports that the Transbay Joint Powers Authority (TJPA), which is managing the effort to extend Caltrain to the Salesforce Transit Center has been awarded $3.4 billion from the Federal Transit Administration to complete the underground tunnels connecting the two transit facilities. The TJPA was reliant on the federal money, and now they’ve secured it. And the tunnel project has a new name, as they’re now calling it “The Portal.”    

They picked a funny week to call something “Portal,” but that’s the new shorthand name.

Image: Transbay Joint Powers Authority 

A rendering of the finished product is seen above, and yes, the Caltrain will be heading into underground tunnels at Fourth and King streets. They’ll arrive at the Salesforce Transit Center two floors below the street-level. As the Examiner explains, “The massive undertaking would extend the Caltrain commuter rail line by 1.8 miles, dig 1.3 miles of underground tunnel, and construct two underground stations to bring Caltrain service from Fourth and King Streets to a six-level underground endpoint.”  

The whole project itself is running a $6.7 billion price tag, so the feds are basically covering half. Counting in the local and state money also lined up, the whole shebang is now two-thirds funded. “There’s only a handful of projects in the United States that have that level of commitment,” TJPA executive director Adam Van de Water told the agency at a meeting last week, per the Examiner.

Image: Transbay Joint Powers Authority 

Though yes, that’s $6.7 billion for an extension of… just nine blocks. But the whole thing is underground, hence the high cost.

And it’s still not determined where the remaining $2.75 billion of that is coming from. The TJPA is hoping for another $1 billion from the state, but that’s not guaranteed, considering the state is running a $28 billion deficit. The Examiner adds that state Senators Scott Wiener and Aisha Wahab are working on a bill that could raise funds through 2026 state tax ballot measure.

The station would be connected to the long-sought California high-speed rail system, which has of course been taking forever to build. But that project has made progress in recent months, with now more than 25 active construction sites in the Central Valley.

Image: SFCTA

The latest estimates still show that the Salesforce Transit Center connection is not expected to be finished until 2032 or 2033, should they even line up the money in the first place.

By the way, this August will see the five-year anniversary of the Salesforce Transit Center’s opening. That opening was famously marred by mishaps and delayed by cracks in its steel beams. Similar delays seem likely to happen with this expansion. But luckily for Salsforce, it would still be called the “Salesforce Transit Center” on that timeline, as Salesforce’s naming rights deal for the facility runs to the year 2042.

Related: High-Speed Rail Could Finally Be Coming to Salesforce Transit Center, But Only If the Feds Kick Down Billions [SFist]

Image: Transbay Joint Powers Authority