SF's Own Second Ave Subway

Not down Second Avenue in the Richmond District, naturally. The title refers to the eighty-year-long history of the as yet unbuilt Subway line under Second Avenue in Manhattan.


This map was drawn in 1931, two years after the Second Avenue line in New York was proposed. I have a copy of this hanging in my hallway, so I was surprised when I noticed the other day that it includes a couple lines that transit enthusiasts would still love to see built.

H-Potrero Van Ness

Left: H-Potrero Van Ness subway proposal (2009)
Right: 1931 proposal (H-line alignment highlighted in red)

In a previous post I proposed a new crosstown subway along Van Ness and Potrero Avenues, connecting to the T-Third light rail line in the Bayview. The Overhead Wire has a similar proposal.

Well we're both late-comers. Transit planners 80 years ago had already laid out the vision for a high capacity transit line along Van Ness and Potrero, connecting to one that would run down Third Street. In 1931, however, the Islais Creek delta had not yet become the industrial zone it is today, and Highway 101 hadn't yet split San Bruno Avenue into two disconnected strips.

Back then the Portola District was booming, so planners passed their line through the neighborhood. Today, however, the Bayview/Hunters Point area is the next big thing, so TOW and I have our subways serving that area.

The 1931 line ended at Paul Avenue, where it met Third Street at a passenger rail station. That station closed in 2005 (but there are plans for a possible new Caltrain station at Oakdale Ave, closer to more Bayview residents).

N-Judah Extension

Top: The Overhead Wire's proposal to run the N-Judah down 19th Avenue
Bottom: 1931 proposal (corresponding alignment in blue)

In TOW's fantasy map, the N-Judah stays underground after entering the East portal of the Sunset tunnel, turning south to travel down 19th Avenue. 80 years prior, planners accomplished a similar alignment with a subway under Irving, which looped around and surfaced before heading South down 20th Ave as a streetcar.

In both cases, a streetcar line is left above ground to serve the Outer Sunset along Judah.

Central Subway

Left: Working plans for the Central Subway
Right: 1931 proposal

The Third Street corridor seems to be pretty much right on track after 80 years. The T-line's been gliding along Third Street since 2005 and work is progressing on the Central Subway (phase II of the T-line). That's an alignment that's been in planners' minds since at least this 1931 map, though earlier plans (through the last couple decades) had the subway running down Third in SoMa and up Kearny to Columbus Avenue.

In current plans the T jogs to Fourth St where it connects Caltrain, Moscone Center, Union Square and Chinatown. Transit advocates may find much to dislike about the way Muni is going about building this route, but a need for some sort of cross-Market subway has been evident for quite a while indeed.

I can spot a couple more ideas from the 1931 map that remain worthy of consideration, and I'll polish up some new maps and post those in the future. But just as in Manhattan's East Side, 80 years of wrongheaded priorities has left us with a transit network that still doesn't serve demand that has existed - and been documented - for decades.

Can we turn the tide now, and give ourselves the 21st Century city we ought to have had well before WWII? Time will tell.