The Spread Of The Sprawl

St. Louisans and Wash U students rightly criticize the city’s anemic public transportation and bike infrastructure. However, this shortage exists in the context of St. Louis’ overbuilt automobile infrastructure. St. Louis sits at the intersection of several major interstate highways that serve as the arteries of a larger network of roads that make up the city’s car dominant transportation network. We take this as given, but our reliance on cars is not inevitable.

It seems as if every business has either a drive-through or a large parking lot; even the public library in my hometown has a drive-through window. In The Triumph of the City, urban economist Ed Glaeser suggests that “the defining characteristic of American cities built in the late twentieth century is their accommodation of the automobile.” America’s embrace of (and dependence on) the car has driven the spread of sprawl. For the purposes of this article, sprawl signifies less-dense, car-centric suburban or exurban areas outside of central cities.

Over the course of the 20th century, structural changes in the economy led to the growth of manufacturing and services over agriculture as the primary sectors of the American economy. These structural trends drove the rise of large cities and metropolitan areas and the decline of rural areas. According to the Census Bureau, the proportion of Americans living in rural areas plummeted over the course of the 20th century, from just over 70 percent in 1910 to under 20 percent in 2000.

Demographic shifts also occurred within America’s growing metropolitan areas. The share of the urban population that lived in city centers fell from about 75 percent in 1910 to around 35 percent in 2000. This trend especially took off with the rise of suburbanization (and sprawl) that followed the end of World War II and coincided with Americans’ enthusiastic adoption of the car as our default mode of transportation.

There is a strong relationship between how people get around and where they live. Without reliable mass transportation or cars, early urbanites had to live within walking distance of their work, which promoted cramped, dense central cities. Streetcars, subways and cars all allow people to live further away. The invention of fast and reliable modes of transportation at the end of the 19th century allowed people to live further away from their jobs.

Suburbs existed long before the advent of car culture and the mass suburbanization. The first significant wave of suburbanization in the late 19th was itself enabled by a previous transportation revolution – the electric streetcar. “Streetcar suburbs,” like University City in St. Louis or Evanston in Chicago, sprang up along streetcar lines that promised a fast and reliable commute from the more spacious suburbs to the city center.

The dynamics of suburbs and suburbanization changed with the creation of cheap, mass-produced homes, the declining cost of cars, and the growth of the road network. These three trends complemented one another and spurred the post-World War II boom in suburbanization. As the chart shows, the share of Americans living in suburbs took off in the 1950s and has not stopped growing since then. As a consequence, America is now a majority-suburban nation.

[su_pullquote]Governments consistently implemented pro-auto policies that effectively subsidized commuting by car at the expense of mass transit systems.[/su_pullquote]The process of post-war suburbanization was shaped by policy decisions at the local, state, and federal levels. Governments consistently implemented pro-auto policies that effectively subsidized commuting by car at the expense of mass transit systems. The comprehensive network of paved roads built during the mid-20th century enabled Americans to sprawl out from city centers into the newly growing suburbs.

In The Rise and Fall of American Growth, Robert Gordon argues that “deliberate urban policy, in the form of street surfacing, encouraged automobile and truck traffic.” Gordon describes how state and local governments built “streets and highways with public funds … by issuing bonds on which the interest was paid by local property taxes.” In essence, this meant that mass transit riders and drivers alike contributed to the construction of a rival mode of transportation.

It is hard for any business to survive when it is forced to subsidize its competition. Private streetcar lines and their riders saw their property taxes fund the development of a competitor: highways. Ultimately, these distortionary policies killed off the streetcar lines that connected older suburbs to the city center and caused commuters to shift towards the car as their primary means of transportation.

To some degree, transportation follows a logic of “if you build it, they will come” (induced demand in economics jargon). The key idea is that increasing road capacity encourages more people to drive. In essence, the highways built in the postwar era created their own demand, while simultaneously undermining older private mass transit systems.

At least symbolically, the root of all anti-density evil is the Interstate Highway System. Authorized by President Eisenhower in the Federal Aid Highway Act of 1956, the 40,000-mile system of roads was largely completed by the end of the 1970s. According to Glaeser, the interstate system enabled “mass suburbanization and the rise of car-oriented cities.”

Nathaniel Baum-Snow studied the effect of the interstate highway system on suburbanization. He found that, over the course of the second half of the 20th century, “one new highway passing through a central city reduces its population by about 18 percent.” This is a huge effect; it implies that in the absence of the Interstate Highway System, the population of America’s central cities would have increased, instead of falling precipitously.

[su_pullquote align=”right”]It is important for our leadership on the world stage and for public health reasons at home that we work to reduce emissions of greenhouse gas and other harmful airborne pollutants.[/su_pullquote]Short of tearing up roads, there is no way to reverse the impact of America’s historic auto-friendly policies. Ripping up highways is clearly a terrible idea; but, going forward, we should stop subsidizing sprawl and instead promote density. Although the United States won’t play a determinative role in stopping climate change, it is important for our leadership on the world stage and for public health reasons at home that we work to reduce emissions of greenhouse gas and other harmful airborne pollutants. Embracing urban density and reducing our dependency on the car is the best path for our future.

The government should invest more in public transportation and stop promoting travel by car. How this policy would look in practice depends on the existing mass transit system in a given city; in New York or Chicago, this would involve modernizing existing infrastructure, with an emphasis on improving on-time performance and reliability. In St. Louis or Sun Belt cities with little mass transit infrastructure, it could mean building out a light rail network and promoting dense, transit-oriented development alongside.

Similarly, cities should invest in more bike (and electric scooter!) friendly infrastructures like protected bike lanes and mixed-use trails. Two-wheeled options complement public transit and can help people more fully move away from cars. At the same time, a tax on vehicle miles-traveled would more directly reduce the amount that people drive. Unlike a fuel tax (which is laudable in its own right), taxing vehicle miles- traveled does not create an incentive to switch to more fuel-efficient cars instead of stopping driving altogether.

It is also important to reduce restrictive zoning requirements in order to permit denser development closer to city centers. As it stands, many cities use zoning laws to impose occupancy restrictions. The Height of Buildings Act in Washington D.C. restricts structures to a maximum height of just 110 feet. As the city’s economy grows (especially after Amazon announced its construction of a satellite headquarters in the region), younger renters have been pushed further and further out into the Virginia and Maryland suburbs. Minneapolis is a model here; at the end of last year, the city ended single family zoning citywide, allowing two and three-unit buildings anywhere in the city, with even denser development possible along transit corridors. Washington D.C. provides an example of what to avoid.

[su_pullquote align=”right”]We should stop promoting sprawl and instead encourage people to give up cars in favor of a combination of mass transit, bikes, and walking.[/su_pullquote]Historically, America’s car-friendly public policies have promoted suburbanization and sprawl. The roads and parking lots required by our car-centric culture take up space, which is why car-focused suburbs are so much less dense than urban centers. Over the course of the 20th century, public policy at all levels of government promoted cars and highways at the expense of other, more environmentally friendly modes of transportation. As we move into the 21st, we should stop promoting sprawl and instead encourage people to give up cars in favor of a combination of mass transit, bikes, and walking.

Michael Fogarty ‘19 studies in the College of Arts & Sciences. He can be reached at michael.fogarty@wustl.edu.