Transit database shows which SF neighborhoods are ‘transit deprived’

Say whatever you like about public transit in San Francisco, at least it’s ubiquitous.

But it’s still not good enough, or so says AllTransit, the transit data-based nonprofit that strives to compare every city in America’s mass transit service to every other city’s mass transit service.

(For the record, AllTransit is a joint venture of two different non-profits—New York’s TransitCenter and Chicago’s Center for Neighborhood Technology.)

In their latest venture, AllTransit has compiled an interactive “Gap Finder” map of neighborhood tracts across America and conveniently color-coded them to determine which have adequate transit service and which are “transit gaps.”

Unsurprisingly, there isn’t a square inch of San Francisco that, except for Treasure Island and the Farallones, is not relatively transit-dense, with 91 percent of the city dubbed adequate.

What’s strange, though, is the areas that perform the worst by AllTransit’s rubric. The areas in red on the AllTransit map—thus most poorly served—include parts of the NoPa, Cow Hollow, and the Mission; and pink zones (only slightly better served) spread across areas like the Marina, Pacific Heights, and the Inner Richmond.

Photo by Justin Sullivan/Getty Images

That seems odd, since your average San Franciscan could name the Muni lines that run through those neighborhoods even if they never ride them. But as AllTransit’s algorithm reckons, the density in those neighborhoods outstrips the service.

As the database’s methodology page explains:

The underserved neighborhoods are those that have transit service that is below average for all neighborhoods with the same mix of demographics, employment, commerce and urban form. [...Is transit in these areas] good enough? AllTransit has to concede that we do not know the answer to this, but rather the gap points out where transit is too low relative to similar neighborhoods.

So, the Mission has a lot of transit. But it has less than other neighborhoods like it in every city in America.

Whether or not this is bad news depends entirely on the degree of demand. As CityLab points out, AllTransit measures potential need based on density and activity. How that translates into actual demand is harder to figure out based on the data.

San Francisco’s “transit gaps” pose a potentially interesting question: Where does the city need more service, and how do San Franciscans decide? The data can show us where it will reach the most people, but it can’t decide our transit priorities for us.

Photo by Justin Sullivan/Getty Images

• Database Compares SF Transit [Curbed SF]
• Gap Finder Map [AllTransit]
• Gap Methods [AllTransit]
• The Problem With Gaps [CityLab]