Dueling congestion reports released

By Eric Sundquist

Two reports issued within days provide contrasting takes on the enduring issue of highway traffic congestion.

One report from traffic-data firm Inrix is an update of previous scorecards that rank world cities for highway delay, calculated by aggregating travel times slower than free flow. This year’s edition adjusts away from the firm’s previously downtown-centric methodology, shuffling the rankings somewhat. But the basics remain—lots of time spent in cars going slower than free-flow, and when that “delay” is multiplied by $14/hour for the U.S., a big implied cost.

Inrix does add a couple of new elements this year. It adds qualitative assessments, by metro area, of the impact non-recurring congestion (aka “incidents”) has; in general, it is “moderate” for the congested parts of the United States. Inrix also provides qualitative assessments of the suitability of bike and transit modes as alternatives to auto travel within metro areas.

As in past years, the report’s effort to explain the phenomenon of congestion and related policy solutions is brief and marred by typos, with some cut-and-paste text from last year’s report, giving it the feel more of a promotion piece than serious research. Inrix, for example, does not dwell at all on induced traffic from highway capacity additions.

In contrast, Transportation for America’s[1] new report looks closely at how the capacity solution has worked, and finds it wanting:

“In an expensive effort to curb congestion in urban regions, we have overwhelmingly prioritized one strategy: we have spent decades and hundreds of billions of dollars widening and building new highways. We added 30,511 new freeway lane-miles in the largest 100 urbanized areas between 1993 and 2017, an increase of 42 percent. That rate of expansion significantly outstripped the 32 percent growth in population in those regions over the same time period. Yet this strategy has utterly failed to ‘solve’ congestion.”

T4A recommends shifting focus away from highway-delay metrics and toward multimodal accessibility, a metric that takes into account land use as well as speed of travel. It also recommends repairing existing networks, making active transportation safer to reduce short car trips, and encouraging denser infill. Like Inrix, T4A praises road pricing and urges policy-makers to do more of it.

T4A, along with Strong Towns President Charles Marohn, will present the report on a March 17 webinar.

[1] Relationship disclosure: Transportation for America is a project of Smart Growth America. SSTI is a co-project of the University of Wisconsin and Smart Growth America.

Eric Sundquist is Director of SSTI.