Previous posts in this series:
Sunshine Through the Gridlock (Jan. 2011)
News Flash: Congestion Still Not Getting Worse (Sept. 2011)
After a long hiatus, the Texas Transportation Institute (TTI) is out today with its latest Urban Mobility Scorecard, a national estimate of the intensity and costs of highway congestion.
The Urban Mobility Scorecard has become something of a piñata among smart transportation analysts, and for good reason. It ranks as “worst” for congestion many of the densely urbanized cities whose residents are least exposed to traffic, due to the prevalence of transit and the shorter length of automobile trips. It exaggerates the economic impact of congestion, as laughably demonstrated by City Observatory’s “Cappuccino Congestion Index.” And previous editions have suffered from methodological flaws. Joe Cortright’s post at City Observatory is a great one-stop shop for the main critiques.
For our part, we’ve focused our attention in recent years (see posts above) on critiquing how the TTI data are spun in the media. Every year, come rain or shine, TTI concludes that congestion is getting worse and is likely to continue getting worse every year on out to infinity – even when the evidence from its own report paints a more mixed picture.
Taking TTI's findings at face value, this year is no exception. Driving is on the increase (though likely more as a result of crashing oil prices than economic growth). And TTI’s figures show that congestion did get worse in most cities last year compared with 2013.
But over a longer time horizon, stretching back to the pre-recession years of the early 2000s, TTI’s numbers show that congestion has hit something of a plateau. Assuming that data from the early years of the TTI report can be accurately compared to more recent figures (something Cortright questions), the average number of hours spent in traffic by an auto commuter is no higher than it was in 2006.
Annual Delay per Auto Commuter (data: Texas Transportation Institute)
The marginal increase in congestion in 2014 is certainly worth noting, but where things get really interesting is when TTI attempts to forecast the impacts of congestion in the future by simply pretending that the last decade didn’t happen, basing its projection instead on trends that prevailed from 2000 to 2005 (the years highlighted in red in the chart above).
The authors explain it this way: “The period before the economic recession (from 2000 to 2005) was used as the indicator of the effect of growth. These years had generally steady economic growth in most U.S. urban regions; these years are assumed to be the best indicator of the future level of investment in solutions and the resulting increase in congestion for each urban area.”
It’s hard to be diplomatic about how wrongheaded this is. The period TTI uses as its best guess of what is likely to happen over the next five years 1) ended a decade ago; 2) was characterized by consistent economic growth that was 3) driven in large part by a massive speculative exurban housing bubble; 4) predated the smartphone, Uber and even (until 2004) Facebook; and occurred 5) during a time when the Highway Trust Fund was still solvent. If you want to argue that gas prices will remain low and the economy reasonably robust forever, fine. But it’s not legitimate to simply assume that America will magically be whisked back to 2002 again.
We do need to give TTI credit on one score. In previous editions of the report, TTI has promoted capacity expansion – especially highway expansion – as the primary antidote to congestion, relying at times on ill-considered and out-of-context analysis to make its point. Today, however, TTI has seemingly recognized that you can’t simply build your way out of congestion. While the report still puts too much emphasis on capacity expansion, it now advocates for a “balanced and diversified” approach to addressing congestion that includes a wide variety of tools. It even acknowledges that, for some areas, congestion might not be seen as a top priority problem.
Which brings us back to the fundamental issue with TTI’s approach to measuring and talking about congestion: context. The $160 billion “price tag” for congestion estimated by TTI is a big number, but it pales in comparison with other costs of automobility, including the $836 billion in economic losses and societal harm caused by motor vehicle crashes each year, the $411 billion households spend on cars annually and $328 billion we spend on fuel to run them -- much less the costs imposed by air pollution and transportation’s contribution to global warming. Congestion is just one of many problems caused by our car-dependent transportation system, and not always the most important or the most costly one. The best responses to it are likely to be solutions that address many of the costs and dangers of transportation all at once.