For some reason–perhaps laziness or force of habit, or engagingly alarmist (‘new records for traffic misery!’) press releases, media outlets across the country dutifully report as fact the whatever new congestion ‘study’ the Texas A&M Transportation Institute releases. The problems are significant: their approach uses bizarre assumptions, questionable data, and despite being produced under the aegis of an institute at a major research university has never been subjected to peer review.
The report, from Texas A&M University, looks at only one factor: how fast traffic moves. Consider two hypothetical cities. In Denseopolis, people live within 2 miles of work on average, but the roads are fairly clogged and drivers can only go about 20 miles per hour. However, it only takes an average of 6 minutes to get to work, which isn’t bad.
On the other hand, in Sprawlville, people live about 30 miles from work on average, but there are lots and lots of fast-moving freeways, so people can drive 60 mph. That means it takes 30 minutes to get to work.
Which city has worse roads? By TTI’s methods, it’s Denseopolis. But it’s the people of Sprawlville who spend more time commuting, and thus have less time to be with their families and for recreation.
The authors continue to report data for 1982 through 2007, even though TTI’s model for those years doesn’t actually measure congestion: it simply assumes that increased vehicle volumes automatically produce slower speeds, which is not necessarily accurate. The report’s data from 2007 and earlier isn’t comparable the data that comes afterwards, and can’t legitimately be used to make claims about whether traffic is better or worse than in earlier periods.
The presumption of the methodology is that our goal–to avoid “waste”–is to have sufficient road space available that the most popular times to travel see no delay whatsoever during peak times. That sounds nice, as long as we temporarily forget that land and money are scarce resources.* What makes the best (and most congested) cities attractive to access is that a)there’s lots of economic opportunity and activity there, and b) they are interesting and attractive places to visit. Ginormous 12 lane highways and acres of parking competes with those values; it’s a boring, ugly land use that generates little revenue. Walkability and human-scale density and cars travelling 60 MPH don’t go together.
Pretty much any time you decide to X at the most popular time to X, you pay for your timing in some way, whether in money, time, or flexibility. For whatever reason, we’ve elected to have a system where commuting by car at peak costs time instead of money. This choice has some cross-ideological appeal; on the anti-tax right the alternative is treated as tax increase; on the left it offends a kind of egalitarian ethos about access to a public good. I see the force of the latter position, but think it’s ultimately mistaken; transforming the cost of peak congestion from a time penalty to a financial one contributes to a number of progressive goals (environmental, of course, but public transit, as buses get stuck in congestion too). But either way, the notion that we should expect this activity to come at any price at all is both unrealistic and entirely undefended.
*The atmosphere’s capacity to store carbon emissions is a scarce resource too, of course, but the underlying logic here would still be deeply flawed even if global climate change turned out to be nothing more than a figment of Al Gore’s fevered imagination.