How should we grade America’s transportation systems?
The big, headline-grabbing transportation metric right now is the Texas Transportation Institute’s Urban Mobility Report, which holds up the lack of congestion as the ultimate sign of a well-functioning transportation system. By that measure, cities like Kansas City, Phoenix, and Detroit — where car commutes can be free-flowing but tend to cover long distances — come out looking great, while large metros that do a better job of providing non-automotive transportation options — like Chicago, Washington, Los Angeles, San Francisco, and New York — look like failures.
But TTI’s narrow focus on congestion has come under increasingly intense scrutiny in recent years, with critics pointing out that it is used to justify road-widening projects that purport to reduce congestion but mainly serve to encourage sprawl and lengthen commutes.
A study recently released by the University of Minnesota presents an interesting alternative to the TTI’s metrics. UMN Transportation Engineering Professor David Levinson recently analyzed metropolitan commuting according to a very different criterion: accessibility, or “the ease of reaching desired destinations.”
Levinson attempted to improve on the TTI report by tracking the time it takes for people in the 51 largest U.S. metro areas to reach jobs. His findings stand in stark contrast to the TTI’s report. Large metros like Los Angeles, San Francisco, New York and Chicago offered the greatest number of jobs within a 10-minute car commute, Levinson found.
While TTI’s methodology penalizes cities for locating homes and businesses close together, because that increases congestion, in Levinson’s analysis, higher concentrations of destinations are rewarded for helping to reduce travel times.
“There are two ways for cities to improve accessibility—by making transportation faster and more direct or increasing the density of activities, such as locating jobs closer together and closer to workers,” Levinson writes.