Diridon Station is planning a major transformation in the coming years (and perhaps decades) as it become the Grand Central Station of the West Coast and boy is there a lot to unpack here. First let's start with the good news. Service will be expanded across the board. Caltrain will triple their service from 4 trains an hour during peak times to 12 in each direction. Capitol Corridor will go from 6 trains a day to 11. ACE is planning one extra train. VTA Light Rail will increase service by 50% and buses by 12%. TAMC will add 4 trains a day to/from Salinas. Last but very much not least, High Speed Rail will have 4 trains per hour in both directions.
So far so good. There are three proposed alignments for the future station improvements. Elevated tracks, at-grade, and stacked. Below are some of the key comparisons and a few renders.
And now the bad news... the cost. Transportation transformation does not come cheap. These improvements are estimated to cost between $2.5 and $13 BILLION dollars. Those are today's dollars, not 2040 dollars factoring for inflation. Also, this doesn't even include BART which is a separate project.
To put the ridiculousness of those costs into perspective, the entire cost of San Jose Mineta International Airport's Terminal B is $1.8 billion in 2023 dollars. The cheapest proposal is more expensive than half of our airport!
The most expensive proposal for one station would build an airport two times the size of SJC. That one station would cost more than the entire four-station BART subway from Berryessa to Santa Clara. It is a completely stunning cost, and not in a good way.