A slightly anxious driver is a safer driver.

I gobbled up the rest of Tom Vanderbilt’s Traffic over the weekend. Every page was rapturously, jarringly fascinating – like, “kid with gleaming eyes and a new dinky car” fascinating. The moral of the story: there is nothing more hazardous than a comfortable driver. Traffic engineers are charged with the Sisyphean feat of integrating safety features into roadways… without giving drivers the impression that they’re on a padded go-kart course where nothing could possibly wrong. Guard rails? Okay, I’ll drive a little faster and maybe send a few text messages. Marked crosswalks? Guess I won’t bother looking for pedestrians anywhere else. Who knew that any branch of engineering was part psychology, part infrastructure? Not me.

Rather than posting one particular excerpt that’s indicative of the whole, here are my favourite factoids:

  • “Pedestrians […] are told that making eye contact is essential to crossing the street at a marked crosswalk […], but at least one study has shown that drivers were more likely to let pedestrians cross when they did not look at the oncoming car.” (33)
  • Motorist-cyclist collisions may be more likely to occur when a cyclist uses arm signals because drivers tend to look for intention cues in the faces (not arms) of fleshy, out-of-car human cyclists. Adding a hand signal to the mix may increase the amount of information a motorist needs to process. (36)
  • Drivers tend to pass closer to cyclists wearing helmets, and further from cyclists who appear to be female. (38)
  • One of the risks motorcyclists face is that motorists driving cars and trucks simply aren’t looking for them – they’re looking [out] for other cars and trucks. (83)
  • In places with more pedestrians, pedestrian fatality rates tend to be lower, because the more pedestrians a driver sees, the more likely that driver is to drive cautiously. (85)
  • Drivers “seated at higher eye heights” tend to speed more than drivers in lower vehicles. A greater tendency to speed adds to rollover risk for drivers of SUVs and trucks. (94)
  • “If we were to drive at night in a way that ensured we could see every potential hazard in time to stop – what is legally called the “assured clear distance” – we would have to drive 20 miles per hour (32 kph). (99)
  • The California Highway Patrol uses codes “to disguise the presence of stalled female drivers, who might otherwise be preyed upon by unsavory men listening to police scanners.” (116)
  • “Many people are under the mistaken impression that roundabouts cause congestion. But a properly designed roundabout can reduce delays by up to 65 percent over an intersection with traffic signals or stop signs.” (124)
  • SUVs are about 14% longer than cars and take longer to accelerate, so they “can create up to 20 percent more lost time” at intersections. (125)
  • “Most people, the world over, spend roughly the same amount of time each day getting where they need to go. […] The daily round-trip commute clocks in at about 1.1 hours.” (131)
  • “‘If you look at trip rates by male versus female, and look at that by size of family,’ Pisarski says, ‘the women’s trip rates vary tremendously by size of family. Men’s trip rates look as if they didn’t even know they had a family. The men’s trip rates are almost independent of family size. What it obviously says is that the mother’s the one doing all the hauling.'” (135)
  • Continue reading A slightly anxious driver is a safer driver.

The more traffic changes, the more it stays the same.

Tom Vanderbilt’s Traffic is pure brain candy for anyone with a bone or ten to pick about infrastructure and active transit. On our tendency to describe vehicular traffic as an amorphous blob:

[We] think of traffic as an abstraction, a grouping of things rather than a collection of individuals. We talk about “beating the traffic” or “getting stuck in traffic,” but we never talk – in polite company, at least – about “beating people” or “getting stuck in people.” The news lumps together “traffic and weather” as if they were both passive forces largely outside our control, even though whenever we complain about it, we do so because we’re part of the traffic. […] We say there is “too much traffic” without exactly knowing what we mean. Are we saying there are too many people? Or that there are not enough roads for the people who are there? Or that there is too much affluence, which has enabled too many people to own cars? (7)

On pedestrians, forever in the crosshairs:

In 1720, traffic fatalities from “furiously driven” carts and coaches were named the leading cause of death in London […] while commentators decried the “Controversies, Quarreling, and Disturbances” caused by drivers “contesting for the way.” Meanwhile, in the New York of 1867, horses were killing an average of four pedestrians a week (a bit higher than today’s rate of traffic fatalities, although there were far fewer people and far fewer vehicles). Spooked runaways trampled pedestrians underfoot, “reckless drivers” paid little heed to the 5-mile-an-hour speed limit, and there was little concept of right-of-way. (9)

And on bicycles, forever vehicles without a home to call their own:

After a couple of false starts, the “bicycle boom” of the late nineteenth century created a social furor. Bicycles were too fast. They threatened the riders with strange ailments, like kyphosis bicyclistarum, or “bicycle stoop.” They spooked horses and caused accidents. Fisticuffs were exchanged between cyclists and noncyclists. Cities tried to ban them outright. They were restricted from streets because they were not coaches, and restricted from sidewalks because they were not pedestrians. (10)

From Vanderbilt, Tom. Traffic: Why We Drive the Way we Do (and What it Says About Us). Toronto: Knopf, 2008. Print.