Archive for November 23rd, 2009

I was intrigued by this line from a new paper by John N. Ivan, Norman W. Garrick, and Gilbert Hanson titled “Designing Roads That Guide Drivers to Choose Safer Speeds”:

The aesthetics or “beauty” of a road environment has also been investigated in relation to traffic safety. Drottenborg (1999) studied the impact of speed on streets that appear as “beautiful” due to the blossoming of cherry trees along the streets in Lund during springtime, and similar streets that lack such beautification. She found that the free-flow mean speed decreased by about 5 percent and the number of vehicles traveling at high speeds between 50-60 km/h decreased by about 12 percent during the cherry blossom period.

One imagines a whole new sub-field of traffic engineering, with myriad questions: Do certain buildings or even architectural styles affect driver behavior? Can beautiful people literally “stop traffic”? Road aesthetics in general is a rather lost art; there’s a whole interesting strand of research from the optimistic 1950s, particularly from the U.K., looking into things like which sorts of road-side plants read most legibly at design speeds.

Of course, in so much of contemporary America, what James Howard Kunstler lovingly calls our “National Automobile Slum,” there’s not much present that would make anyone slow down (just the opposite really); indeed, the only seeming role of aesthetics in these environments is to transmit basic information (e.g., branding messages) at highway speed. When one actually gets out of the car in something like a big-box parking lot the effect is rather soul-crushing.

The aforementioned paper (which looked at a variety of locations in Connecticut), by the way, found that, perhaps not surprisingly, “drivers slow down where the road feels “hemmed- in” or there is noticeable street activity, and they speed up where the road feels “wide open” or street activity is less noticeable. This finding is not surprising, but these relationships are quite strong in the observed data, and it is a useful result to isolate this short list of factors that are significantly correlated with actual vehicle running speeds.”

And speaking of aesthetics, roads, and Connecticut, the Merritt Parkway is in trouble. The Depression-era Merritt Parkway had made the World Monuments Fund list of endangered global treasures, joining Machu Picchu, among others.

Built in the 1930s, the Parkway was intended for cars going a leisurely 35 mph, not today’s high speeds. More than simply a road to get drivers from one place to another, it provides a uniquely relaxing experience, said Jill Smyth, executive director of the Merritt Parkway Conservancy, the nonprofit that nominated the road for a slot on the World Monuments Fund list. She touted its gently rolling topography, quintessentially New England landscape and historic stone bridges…

…Newman said he and other Merritt fans are currently at “loggerheads” with ConnDOT over a plan that is underway near Trumbull, Conn., which will restore 12 bridges, but also involves the removal of many trees.

The Merritt is a case where the presence of trees and aesthetics doesn’t seem to affect speed choice for many drivers — I’m always amazed at how fast people pass me. I’d hate to see the Parkway turned into some sterile version of I-95 because of the actions of a few people driving, as the police summons puts it, “too fast for conditions.”

NHTSA has predicted that electronic stability control “would save 5,300 to 9,600 lives and prevent 156,000 to 238,000 injuries in all types of crashes annually once all light vehicles on the road are equipped with ESC.”

This article brings up a few of the reasons why that estimate — as with previous technological interventions — might be high (even if there is still a net safety gain). One of the operative questions is how aware people are of the presence of ESC, and whether they can actually feel its effects, and what new problems owing to unintended consequences might arise.

But not everyone sees stability control as a cure-all that will prevent all road crashes.

“Turning the wheel into the slide can tell the system its task has finished and it may cease its assistance,” Gambold says.