URBAN DESIGN | Transit Follows Density
Southern leaders must commit to density as an unavoidable prerequisite to viable transit.
Written By Phil Veasley
“Why should we waste money on transit when nobody rides it?” This is a question every Southern agency faces when proposing adjustments to transit systems. Or when proposing new ones. It’s frustrating to encounter, but when you dig a little deeper, there is some merit to the assumption that nobody rides transit in the South. For one thing, ridership is paltry compared to larger, denser, older cities. Of the major rail systems in the US, only Atlanta is the only system in the Southeast that cracks the top 10 in terms of ridership. The sprawling postwar nature of Southeastern metropolitan areas plays a huge part in this. In addition, we can only get so far by trying to bring transit to the people. In reality, our focus needs to shift to maximizing density around our current system.
What do transit-rich cities such as New York, Chicago, Boston, San Francisco, London, Tokyo, and others have in common that Southern cities don’t? Density.
Density and Ridership by Transit-Rich City:
When you control for other factors—economy, wealth, climate—there is one common constant: Density is the common denominator of transit viability. On this logic, there is a case to be made that transit advocates frustrated with their metro’s ability to build or expand transit should refocus their energies on building dense nodes capable of supporting transit first. While this may include corridor preservation, or bus service, it allows cities to develop incrementally, as they always have.
Transit Thresholds
Let’s quantify what this density looks like. It’s unrealistic to expect the South to have the density of New York, but let’s consider the possibility of having about half the density of the other major cities mentioned above. Thinking along these lines, to make transit viable, cities would need a minimum of 7,500 people per square mile (or about half the density of Boston or London). This exists just about nowhere in the South. Densities required for rail start at double this threshold. As shown in the table below, by these standards, Southern cities have, at best, one quarter of the density required for rail.
Southern City Density versus Density of Transit-Rich Cities:
Potential Southern City Population with Increased Density:
While it is likely unattainable to develop Southern cities to this density anytime soon, it may be possible to intensely develop the walksheds surrounding each existing transit station. Considering a half-mile radius around each one, a density of 80 employees and 15 households per acre should be considered the minimum to create a successful urban environment for transit according to PlanITMetro.
Even the South wasn’t always this bad. As explored by ThreadATL, the City of Atlanta had a density of over 8,500 people per square mile in 1940 and a city limits area of 35 square miles. This enabled the modest network of streetcars to serve nearly every resident within the city. While the size of the city limits has today swelled to 137 square miles, the density has plummeted to 3,500, making it hard to realistically serve most people via rail.
In a region where it’s hard to build expensive transit systems, the South does itself no favors by suffocating density.
This walkshed map with MARTA rail overlaid on top paints a bleak picture of walkability in Atlanta. Outside of a solid glob around the Downtown core, walkability is confined to areas of strip malls—not really walkable at all. In addition, there is no evidence of Transit-Oriented Developments (TODs) around the stations.
Although nodal density this is something MARTA has turned its focus to, there’s still a way to go. At the moment, it is a clear failure—a lost opportunity to urbanize and to make a real place. If we were able to fully build out the walkshed of each MARTA station to the full density of 15,000 people per square mile (replicating a city like Boston or London), that area alone would be home to nearly 500,000 people.
In the early 1900s, the cities of Raleigh and Durham in North Carolina’s Triangle region had a network of streetcars. Now, the only train that comes is the Amtrak, which runs fewer than five times a day.
In a region where it’s hard to build expensive transit systems, the South does itself no favors by suffocating density. One Southern city has gotten TOD right nearly from the jump. The success of Charlotte’s station area planning is worth discussing—it’s one place where the density has come before the Transit. But that’s a deep dive for another time.
Phil Veasley is the Kronberg Fellow on Transportation and Affordability. He’s a multimodal transportation engineer working on projects throughout the Southeast that build places for people to move and thrive. Follow him on Twitter @Urban_Connector.