We know what the people of San Francisco want in terms of subway design (a Geary line, our kingdom for a Geary line), but what is the city actually planning? Monday’s meeting of the Land Use and Transportation Committee heard plans for subways running every which way. One public speaker even pitched a waterway tunnel to Treasure Island.

We’ll probably have to stick a pin in that one for now, but the fundamentals of the idea are maybe not as crazy as they sound. After all, a lot of housing is going into the island in coming years, and the city has got to start planning transit to match development rather than chasing after it decades later.

"Once we opened the Market Street subway we just stopped," said Supervisor Scott Wiener. "It’s been nearly 40 years and we have not opened one additional inch of subway."

Last year the supervisor slapped a piece on Medium titled "San Francisco Should Always Have a Subway Under Construction," so we can imagine he spends no small amount of time thinking about this. The new Central Subway corridor project is even now beavering away under the streets, but Wiener fears that the city might simply stop again once it’s finished.

The city’s new Subway Master Plan is due at the end of the year, with Monday’s meeting serving as a checkpoint. In addition to much-in-demand routes to the west side, planners are mulling routes connecting 16th Street to Bayview, splitting the N Judah to run underground through SoMa, pushing the T all the way to Fisherman’s Wharf, and moving all Muni rail completely underground to improve their reliability and let longer trains run.

In all, tentative designs propose "tripling the network we have today," according to transit planner Michael Schwartz.

To commute-weary San Franciscans wondering why it’s taken this long to even talk about expanding our comparably puny tunnel network, this is "wildest dreams" kind of talk. The notion of a second Transbay Tube and a BART connection to the capital corridor even came up.

Of course, the awkward subject of precisely how we’d pay for all of this inevitably came to rain on the collective parade eventually. The final proposal will probably be much less ambitious than everything talked about now, but why not let the people dream? It’ll keep us busy while we wait for that N Judah.