Skip to Content
Streetsblog New York City home
Streetsblog New York City home
Log In
Brooklyn

‘Triboro RX’ Could Provide More Transit Opportunities

The “Triboro RX” and New Transit Riders by Origin (Michael Frumin, 2007)

For the Regional Plan Association, Michael Frumin visualized their plan for a rapid transit line in Brooklyn, Queens, and the Bronx that could be built almost entirely on pre-existing rail and would connect with at least twenty existing subway lines. The "Triboro RX", which originated in the 1996 Third Regional Plan, could provide effective transit between these boroughs at a fraction of the cost of most transit projects.

Working with Jeff Zupan and Alexis Perrotta, I helped to develop a possible alignment for the Triboro RX, and a crude estimate of what levels of initial commuter ridership one could expect to see if it were built. At the end of the day, we can comfortably say that at least 76,000 New Yorkers (including 32,000 diverting from other modes of transportation) would use the Triboro RX to get to and from their jobs every day. This number that is quite competitive with many existing lines, and without ever touching the island of Manhattan.

At the heart of our ability to make this estimate is the Journey-to-Work data published by the census -- counts of commuters between every census tract and every other census tract in the city. Given these flow data, the shape of the subway network with and without the Triboro RX, and a rough model of how people make travel decisions on public transportation, it's not so hard to guess which subway riders would use a new transit line if it were built. Estimating new transit riders is more nuanced, but we did our best with limited resources.

To create these transportation models, Frumin used one of The Open Planning Project's software projects GeoServer. Take a look at the fruits of Michael's labor:

How would the TRX tie into congestion pricing? The graphic above shows that the TRX would do a great job of providing mass transit to unserved communities in the outer boroughs.

Stay in touch

Sign up for our free newsletter

More from Streetsblog New York City

Friday Video: Meet the Subway’s Straphanger-Free Trains

We've all seen them. Now, thanks to YouTube's "Half as Interesting," we can tell you the purpose of each one.

October 3, 2025

The MTA Is Headed To The Lab To Design The Ridgewood Busway

A filthy private road underneath the elevated M tracks could become a gleaming bus-first corridor.

October 3, 2025

Friday’s Headlines: Good News Edition

The Department of Transportation reports that traffic deaths are way down through the first three quarters of 2025. Plus other news.

October 3, 2025

‘Bean-Counting Street Safety’: Advocates Blast Gale Brewer’s Daylighting Flip-Flop

The Upper West Side pol's inconsistent safety record is getting a second look from activists who once supported her.

October 2, 2025

There’s Good Science Behind the Human Craving for Livable Streets

It's time to understand the science of pedestrian-friendly cities. Or, why streets should be designed like gardens.

October 2, 2025

Thursday’s Headlines: Mourning Becomes Enforcement Edition

Why were cops ticketing cyclists at the very intersection where a bike rider was killed by a driver on Saturday? Plus other news.

October 2, 2025
See all posts