In the 1950s and ’60s, streets that once flowed both directions were converted into fast-moving one-way thoroughfares to help cars speed through town — but this had unintended consequences:
In John Gilderbloom’s experience, the notorious streets are invariably the one-way streets. These are the streets lined with foreclosed homes and empty storefronts, the streets that look neglected and feel unsafe, the streets where you might find drug dealers at night.
“Sociologically, the way one-way streets work,” he says, “[is that] if there are two or more lanes, a person can just pull over and make a deal, while other traffic can easily pass them by.”
It’s also easier on a high-speed one-way road to keep an eye out for police or flee from the scene of a crime. At least, this is the pattern Gilderbloom, director of the Center for Sustainable Urban Neighborhoods at the University of Louisville, has observed in San Francisco, in Los Angeles, in Houston and Washington…
I always thought they were simply annoying, but now researchers have collected data about one-way streets and the problems they cause:
In 2011, Louisville converted two one-way streets near downtown, each a little more than a mile long, back to two-way traffic. In data that they gathered over the following three years, Gilderbloom and William Riggs found that traffic collisions dropped steeply — by 36 percent on one street and 60 percent on the other — after the conversion, even as the number of cars traveling these roads increased. Crime dropped too, by about a quarter, as crime in the rest of the city was rising. Property values rose, as did business revenue and pedestrian traffic, relative to before the change and to a pair of nearby comparison streets. The city, as a result, now stands to collect higher property tax revenues along these streets, and to spend less sending first-responders to accidents there.
Gilderbloom and Riggs have also done an analysis of the entire city of Louisville, comparing Census tracts with multi-lane one-way streets to those without them. The basic pattern holds city-wide: They found that the risk of a crash is twice as high for people riding through neighborhoods with these one-way streets. The property values in census tracts there were also about half the value of homes in the rest of the city.
Some of these findings are more obvious: Traffic tends to move faster on a wide one-way road than on a comparable two-way city street, and slower traffic means fewer accidents. The rest of these results are theoretically connected to each other in complex ways.
(Hat tip to Tyler Cowen.)