[Randomguy34]

Part of me wonders if it would be cheaper to convert BART to standard gauge and have rapid & regional transit share tracks, rather than build two new tunnels. A new Transbay, 2-track tunnel would be comparable to NYC's Gateway Tunnel, which is expected to cost more than $16 billion. Two tunnels then could be $32 billion.

Even if the costs of converting to standard gauge and buying new rolling stock are comparable to a second tunnel, it would certainly be better from an operation standpoint. It would help unify the Bay Area's disconnected rail systems, which could provide new routes and increased frequencies. A cheaper alternative could be to have BART experimenting with dual gauge tracks