Congress has done its job, such as it is, and passed a transportation bill. Now it’s handed off the policymaking to U.S. DOT, which must issue a raft of rules, definitions, and guidance to accompany the new law, known as MAP-21.
The wrong way to measure travel performance: "Travel Time Index" awards a better score to Charlotte than Chicago, even though commutes in Chicago are shorter, because drivers in Charlotte spend a higher percentage of their time in free-flowing traffic. Graphic: CEOs for Cities
According to sources with intimate knowledge of this process, much depends on how DOT decides to measure congestion. New performance measures for the Congestion Mitigation and Air Quality Improvement program (CMAQ) — and quite possibly for the entire national highway system (depending how they define “roadway performance”) — require a working definition of congestion.
If the agency follows the prevailing orthodoxy, states could be rewarded for wasteful highway spending. If it adopts better measurements, smarter investments and less wasteful spending will follow.
The CMAQ measures will also require a definition of “cost-effectiveness,” a related but somewhat separate can of worms.
U.S. DOT Should Include Distance Driven in Any Measure of Congestion
Performance measures in the MAP-21 law have been criticized for being toothless, since many of them don’t have consequences attached. However, there is still the possibility that state performance rankings could be made public. And a spotlight on state failures could be an effective way to encourage good decisions.
Streetsblog asked Joe Cortright for his advice to DOT officials struggling to define congestion. Cortright is an economist and senior policy advisor for CEOs for Cities. In 2010 the organization commissioned him to write Driven Apart, a critique of prevailing methods of measuring congestion. His words of wisdom for U.S. DOT: “Don’t make the mistake the Texas Transportation Institute makes.”
TTI’s Urban Mobility Report, released every year, invariably gives top honors to places that have overbuilt road capacity. The institute measures congestion only by looking at the degree to which traffic slows down people’s commutes. The problem with that, Cortright says, is that “you end up rewarding places that encourage people to drive longer and longer distances, and then you look at those long distances that they’re traveling, and say because they’re moving at a relatively higher speed much of the time that they’re driving, that the system is somehow performing better.”
Over the past few years, U.S. DOT has been very deliberately working hand-in-glove with HUD and the EPA to treat transportation and land use as one cohesive system. It only makes sense that the agency use the same ethic in measuring roadway performance and congestion. By doing so, DOT would have to acknowledge that a long commute along miles and miles of free-flowing highways is no bargain compared to a short commute in dense traffic, not to mention an even shorter commute on transit.
Clark Williams-Derry, research director for the sustainability-focused Sightline Institute, suggests that congestion may simply be the wrong thing to measure. “Focusing on congestion is like, in a basketball game, focusing only on the number of assists you get,” Williams-Derry said. “It’s an interesting fact, but it doesn’t tell you the final score.”