The Implications of Peak Car on Highway Construction

An article in New Geography saw some attention several weeks ago by claiming that we can build our way out of congestion. One particular passage saw the most mileage:

“In a world of peak car, where traffic levels are flat to declining on a per capita basis, induced demand no longer holds court, certainly not to the level claimed by those who believe it’s pointless to build roads.”

Before taking on this quote directly, let me first acknowledge that the article (to its credit) caveats its own statement. The author is not calling for a new era of highway building. Instead, he issues a call for “urbanists and policy makers of all stripes [to] think about the full implications of peak car” and to develop a more nuanced approach to supporting transit improvements over highway development.

Consider this post an answer to that call.

To begin with, the causes of peak car have been misrepresented. Despite the continual stream of articles that say 'Millennials Hate Cars,' in fact the trend is a general motion toward dense development nationwide. Heavy investment in highways would slow or even reverse this trend – a policy the US and the globe simply can't afford.

Moreover, researchers at UCLA have called into question how much of the VMT reduction can be credited to urbanization. According to their finding, a majority of the VMT reduction is not driven by urbanization but by an inability to afford cars. Highway construction will reduce congestion only as long as the great American wealth gap stays intact.

Indeed, an article in Planetizen has already debunked the notion that highway building is a solution to congestion, so I won't belabor the point.

Instead, let me emphasize that the real issue with the New Geography article is not that it comes to poor conclusions, but that it asks the wrong question. The primary goal of transportation projects should not be congestion abatement. Transportation infrastructure shapes the land use of our cities, and the land use shapes everything else: from social mobility to environmental footprint. Indeed, even if VMT plummets, expanding the world's largest highway system is still a poor use of public money.