An Alternative to Congestion-Based City Rankings
The Texas Transportation Institute’s “Annual Mobility Report,” which rates highway congestion in major urban areas across the United States, probably gets more press attention than any other piece of transportation research.
These city rankings assume that urban transportation policy should aspire, first and foremost, to eliminate motorist delay. Many press outlets pick up the report’s findings and rush to the conclusion that urban areas need wider roads or more highways. In recent years, critics of the report have convincingly argued that the absence of congestion is a poor benchmark for urban transportation systems. It doesn’t even take into account the total amount of time that people spend driving.
An alternative was put forward earlier this year University of Minnesota engineering professor David Levinson. Levinson has developed a system based on “accessibility” rather than congestion. The benefit of Levinson’s metric is that it takes into account the distance between destinations, and how that affects the ease of getting where you want to go. This overcomes a crucial weakness in the TTI report, although one drawback of Levinson’s measure, currently, is that it only factors in accessibility by car.
Now Levinson’s system will come out in a very media-friendly form: annual rankings. Earlier this month the University of Minnesota’s “Accessibility Observatory” announced that it will release these city rankings, with support from the Minnesota Department of Transportation and the McKnight Foundation. Hopefully it will get as much attention as TTI’s.