Skip to Content
Streetsblog USA home
Streetsblog USA home
Log In
Network Roundup

Is Your City Making Full Use of Existing Transit Investments?

10:51 AM EDT on April 27, 2015

In Chicago, fewer people are living near transit, even though rising rents say demand is high. Graph: Metropolitan Council
In Chicago, fewer people are living near transit, though rising rents indicate demand is high. Graph: Metropolitan Council
false

Chicago's rail transit infrastructure has a lot of unused capacity, Yonah Freemark wrote last week on the blog of the Metropolitan Planning Council, and making use of it might be cheaper and easier than expanding the system.

Some of Chicago's most transit-accessible neighborhoods are barely growing, but rents are rising fast, Freemark reported, an indication that additional transit-oriented housing could be supported. Unfortunately, zoning laws limit new construction in these areas, says Freemark, so countless would-be transit riders move to the suburbs or other regions, outside the reach of transit service.

Inspired by that article, David Levinson at Streets.mn looked at how much additional capacity there is on Minneapolis's new Green Line -- one of the biggest transit success stories of last year -- which carries about 38,000 riders daily. Depending on how you calculate capacity, there's actually quite a bit to work with, says Levinson.

This measures capacity in terms of daily boardings. Daily miles traveled is another measure, and is independent of the length of trips. To calculate this we use the following equation:

Capacity = (Hours of Operation)*(Trains/Hour)*(Cars/Train)*(Capacity/Car)*(Stations – 1) * (Trip Length) * (Directions Operating).

At any rate, the attached table shows some surprisingly high numbers, up to 7 million (under the admittedly silly unconstrained scenario (A) where people only ride the train for 1 stop before alighting, trains run for 24 hours a day, and people are standing at near crush capacity), with more plausible numbers in the 255k territory, assuming everyone gets a seat, but you can run at 5 minute headways (C). Here we are limited by capacity in one section (downtown Minneapolis), which does run at 5 minute headways, but splits the capacity between the Green and Blue lines.

The main point is that there is a lot of capacity on the Green Line yet to go, even if you only run 18 hours a day, and you expect everyone to have a seat, and run at today’s 10 minute headways (which is all today’s fleet can support, to increase headway we either need to increase speed greatly or add vehicles), and assume the average trip is 7 stations (Aaron Isaacs informs me it is 3.5 miles, which at 1/2 mile spacing is about 7 stations) (83,314 – scenario D). At the other end of the spectrum, if everyone expected a seat and was riding from Union Depot to Target Field, the capacity would only be 32,400 with today’s frequencies.

Since Minneapolis has additional capacity on its new rail line, and there's a lot of developable land along the corridor, Levinson wonders: "Why are new corridors being subsidized for development?"

Elsewhere on the Network today: The Wash Cycle shares a photo from San Francisco showing how a bump-out makes a handy spot for a bike corral. BicycleLaw.com discusses the stubborn resistance to bike transportation in Georgia. And Prince George's Urbanist evaluates efforts to make a rail hub at New Carrolton, Maryland, more urban and transit friendly.

Stay in touch

Sign up for our free newsletter

More from Streetsblog USA

NYC Debuts Public E-Bike Charging for Delivery Workers

Finally, they’re taking charge! The city’s first public e-bike charging station opened in Cooper Square on Thursday — the start of an overdue six-month pilot that is part of a “Charge Safe Ride Safe Action Plan” for delivery workers that Mayor Adams announced last year.

March 1, 2024

Friday’s Headlines Have Questions

What's an optimal rebate to get people to buy e-bikes without wasting money on those who were going to buy one anyway?

March 1, 2024

To Recruit Transit Workers, More Than Just Higher Pay Is Needed

Labor shortages continue threatening public transit systems, and a new report adds another layer to the conversation.

February 29, 2024

Talking Headways Podcast: Streets for Skateboards

Aaron Breetwor on skateboards for transportation and designing streets for safer skateboarding.

February 29, 2024

Agencies Need to Use Federal Funding to Buy Land for Transit Oriented Development

Transit agencies do not prioritize transit-adjacent housing development often because they lack funding to acquire land.

February 29, 2024
See all posts